Name: DCS 12V 120AH (LITHIUM)
SKU: DCS-12V-120AH
Availability: InStock

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DCS 12V 120AH (LITHIUM)

SKU: DCS-12V-120AH

DCS 12V 120AH (LITHIUM)

Ultra-Safe

Explosion-proof / No leakage

Stable

Low Internal Resistance / Proven Stability

Long Life

Ultra-long cycle life

Guaranteed A Grade

Contracted A Grade cell supply

There has been some very nice advances in the lithium battery cell market over the past 12 months. For the first time premium high end lithium iron phosphate battery cells have become commercially available that had previously been exclusively produced for the elite companies in the military space and government departments. These cells achieve 4000 cycles after only 20% capacity fade. So if you convert that to the very misleding ‘cycle life’ which some claim 4000/5000 cycles. These new cells are in the 8,000-10,000 cycle life range.

Availability: In Stock

Original price was: $1,495.00.Current price is: $1,399.00.

Already last year in 2023, DCS commercialised this major cell chemistry advancement right across our entire battery range. Meanwhile, fully completing our GEN3 Battery Management System program and all software development back in 2022. What does this all mean? It means for all our batteries sold and distributed world wide we are managing less than 0.2% defects for both the combined battery cells + electronics (end product). Not bad for a little Aussie tech company. Which places us in the top 3 brands in the world for 12V lithium batteries.

We have now expanded distribution across the Northern America’s, Europe, Africa, Middle East and of course Australia.

As a special thanks to our loyal customer base and dealer network and international friends and partners – we have designed and released our new 12V range of slim line batteries. Which feature our EV cell pack design, which means the cylindrical battery cells are fully submerged and coated with special cell interface resins. What do these resins exactly do? Well it means these batteries can run for significantly longer duty cycles. So more continuous power output with little effect on the cycle life.

This makes these batteries superior for the most astute and fussy of customers demanding the very best batteries. So that they can travel across the top end without issue and know their assests are humming along without any concerns.

DCS 6AWG 230mm Parallel Cables with M8 Ring Terminals

Click Here for more information

Specifications:	–
Nominal Voltage	12.8V
Nominal Capacity (1Hr)	120Ah
Case Dimensions (L x W x H)	328mm x 171mm x 215mm
Weight	14.60 Kgs
Cycling voltage	11.5 ~ 14.6V
Charge voltage	14.0 ~ 14.6V
Float Voltage	13.5 ~ 13.7V
Maximum Charge Current	120A
Recommended Charge Current	≤80A
Maximum Discharge Current	≤200A Continuous
DCS BMS (internal)	DCS active cell management system, over/under voltage, over current charge/discharge, low/high temperature protections, satisfies the AS/NZS 3001.2:2022 lithium battery standards
Cell Chemistry	3.2V 20Ah Cylindrical LFP (LiFePO4)
Cycle Performance	4000 cycles @ 100% DOD ≥ 80% Capacity Retention @ 25°C
LCA	1000
Ingress Protection	IP54
Case	ABS (flame retardant plastic)
Operating temp Range	-25°C to 80°C
Terminals	Top Mount M8 Stainless steel / Copper
Parallel Connections	Up To 10
Series Connections	No
Warranty	4 years \| 3 years under bonnet
Certifications	UN 38.3, UL 1642, IEC 62133 & 62619, CE

DCS Lithium batteries 12V 120Ah & 12V 180Ah Overview comparison

How to configure the DCS 12V 120Ah Marine batteries and the DCS 12V 80Ah Extreme batteries into any vessel

DCS Lithium Battery Safety & Reliability

DCS 40135 & Tesla 4680 battery cell cycle testing comparison

DCS HIGH PERFORMANCE 2C CHARGE & DISCHARGE CURVES

”TEXT”

Discover Long-Lasting Power with the DCS Lithium Ion Battery 120ah

The DCS lithium ion battery 120ah powers solar systems, RVs, or even electric vehicles with immense energy over long durations. The battery lasts longer than lead-acid batteries because of the unique technology known as lithium iron phosphate (LiFePO4), which enhances its performance. Its strong design allows it to handle deep discharges, so you won’t have to worry about replacing it often.

This battery can last up to 4000 complete charge-and-discharge cycles, even at 100% discharge, which means it’s very efficient and saves you money over time. Plus, it’s lightweight and doesn’t lose its charge quickly when unused. Whether you’re powering your home, RV, or gadgets, this battery is an innovative and dependable choice for your lifestyle.

Advanced Technology for Unmatched Performance – Lithium Ion Battery 120ah

The DCS lithium ion battery 120ah uses advanced technology to give you powerful energy storage. It’s designed to be safe, efficient, and easy to use, making it perfect for all needs. Its compact size and high energy capacity make it an excellent choice for portable and stationary setups.

By choosing the DCS lithium-ion battery 120ah, you’re getting a reliable energy source that works smoothly and meets your needs, no matter where or how you use it.

Uninterrupted Power Backup with a 120ah Deep Cycle Battery

When you need reliable power backup, the DCS 120ah deep cycle battery is an excellent option for homes and businesses. It provides steady energy storage to keep things running during power outages or off-grid setups. This battery is designed to handle deep discharges, which means your devices will stay powered without interruptions.

Built for tough use, the DCS 120ah deep-cycle battery is perfect for various jobs, like powering solar systems or tools and appliances in remote areas. It’s durable and dependable, making it an excellent choice for anyone who needs consistent energy.

Monitor, Manage, and Optimise: DCS 120ah Deep Cycle Battery with Smart App

The DCS 120ah deep cycle battery has smart technology that makes monitoring and managing your power easy. With the DCS mobile app, you can check your battery’s charge level, voltage, and overall health right from your phone. This handy feature helps you stay informed and take care of your battery so it lasts longer.

The app also provides helpful tips and alerts about charging cycles and environmental conditions. This information will help you use your battery effectively and maintain its high quality. Furthermore, getting the DCS 120-ah deep cycle battery means getting all the ease and sophistication of modern technology in combination with reliable power management.

Power Your Off-Grid Setup with High-Performance 120ah Deep Cycle Batteries

Take your off-grid setup to the next level with DCS 120ah deep cycle batteries. These batteries are made to work well in remote areas and are perfect for solar systems. With a large 120 amp-hour capacity, they can store plenty of energy to power your appliances, even without sunlight.

The DCS 120ah deep-cycle batteries are tough and built to last. They handle harsh conditions while giving steady power. Whether using them for your RV, cabin, or backup power system, these batteries are a dependable choice.

120ah Deep Cycle Batteries – Capacity Retention

The DCS 120ah deep cycle batteries are known for holding their capacity well over time, making them a great choice for energy storage. These batteries are designed to handle deep discharges without wearing out quickly, giving you long-lasting and reliable power.

Here’s why these batteries stand out:

They can go through thousands of charge cycles without much wear.
They hold their charge for a long time when not in use.
These products are designed to withstand shocks as well as harsh climatic conditions.
They can cater for all kinds of energy needs.
To cater for safety and efficiency, they are made with high-quality materials.

With deep cycle batteries of DCS 120ah, you can rest assured that your energy needs will be fully satisfied.

Effortless Energy Management with Deep Cycle 120Ah Batteries

The DCS deep cycle 120Ah battery makes managing your energy easy for home and business use. It uses advanced technology to give you reliable power and works with the DCS mobile app for better control. The application monitors the battery level, temperature, charge cycles, and usage patterns in real-time.

This ability makes energy efficiency easy to manage while ensuring the battery lifespan is maximised. It is reliable whether you have solar systems or use off-grid power systems with the DCS 120Ah battery.

Deep Cycle 120Ah Batteries – Ideal for Solar and Off-Grid Systems

The DCS deep cycle 120Ah battery is excellent for solar and off-grid systems. It stores energy from the sun during the day, so you can use it whenever you need power. This is especially useful for remote areas where regular power isn’t available.

Key benefits of the DCS 120Ah battery:

Performs well in all kinds of weather.
It lasts a long time with many charge cycles.
Works seamlessly with solar power systems.
Holds its charge for extended periods.
Comes with innovative features for easy monitoring through the DCS app.

Choosing the DCS deep cycle 120Ah battery gives you a reliable, efficient energy storage solution perfect for any off-grid or solar setup.

Experience Unmatched Storage with the Advanced 120 Ah Lithium Battery

If you’re looking for a battery that delivers more cycles, stability, and better overall performance, the 120 Ah lithium battery from Deep Cycle Systems is the smart choice. Designed with LiFePO₄ chemistry, this unit offers a perfect balance between compact size and powerful output—ideal for solar systems, mobile homes, caravans, or even commercial backup setups.

Its smart internal BMS ensures protection against common battery risks like overcharging, temperature fluctuations, and voltage spikes. With long-term cycle life and zero-maintenance operation, this battery is more than just a power source—it’s peace of mind in a box. The 120 Ah lithium battery gives you consistent energy wherever and however you need it.

Why a 120 Ah Lithium Battery is the Ideal Fit for Modern Energy Setups

The 120 Ah lithium battery adapts easily to today’s dynamic energy demands, offering flexibility and high output across different applications.

Delivers reliable power even after thousands of charge cycles
The slim form factor fits into vans, utility trays, and home systems
Zero maintenance—no fluid top-ups or corrosion checks
Supports solar, vehicle alternator, and AC charging
Maintains full voltage until near depletion

Whether you’re upgrading a home setup or building an off-grid rig, the 120 Ah lithium battery provides long-lasting energy without hassle.

Dependable Power in a Compact Size with 120Ah Lithium Technology

When you need serious energy in a small space, 120Ah lithium is the battery tech that gets the job done. At Deep Cycle Systems, we’ve refined this format to deliver power where and when it matters—without the bulk, weight, or maintenance of outdated battery types. This battery is used in everything from caravans to marine builds and backup systems.

It’s not just about storage—it’s about resilience. Our 120Ah lithium battery performs under heat, vibration, and consistent load. You get clean voltage, deep discharge performance, and thousands of cycles with minimal fade. It’s efficient, compact, and engineered to simplify your power system without compromising output.

Where 120Ah Lithium Excels in Off-Grid and Mobile Systems

A reliable 120Ah lithium battery changes how you approach energy on the move or away from the grid.

Lightweight enough to reduce GVM strain in vehicles
Holds charge during long periods of inactivity
Seamlessly integrates with DC-DC, solar, or shore charging
Withstands rugged travel without performance drop
Safe for tight or enclosed installs with no venting needed

Whether camping, cruising, or powering gear remotely, 120Ah lithium delivers stability and freedom to go further.

Superior Performance from the DCS Lithium 120Ah Battery

Regarding long-term battery value, the DCS lithium 120Ah battery is in a league of its own. It’s built using advanced cylindrical LiFePO₄ cells, submerged and resin-coated for added strength and cycle life. What does that mean in practical terms? You get thousands of reliable cycles, steady power output, and almost zero voltage drop—even under load.

This battery is perfect for users who don’t want to compromise quality. Whether powering an off-grid setup, running tools in the field, or keeping your 4WD kit charged, the lithium 120Ah battery delivers every time. And thanks to the DCS active BMS, you can count on smarter battery management from the inside out.

How the Lithium 120Ah Battery Handles High-Demand Applications

Need to power equipment or devices with high surge or constant load? The lithium 120Ah battery steps up without hesitation.

Delivers up to 200A continuous discharge—ideal for inverters or fridges
Manages heat and load with no performance dip
Charges fast with up to 120A input supported
Remains stable during vibration or outdoor use
BMS includes low/high temp and voltage protection

When conditions are harsh, the lithium 120Ah battery keeps powering through—built tough for people who expect the best.

Long-Life, Fast-Charging Lithium Ion Battery 120Ah for Off-Grid Living

If you’re living remotely or planning an off-grid setup, the lithium ion battery 120Ah offers a perfect blend of reliability, capacity, and durability. Built with advanced LiFePO₄ chemistry, this battery delivers consistent power for everything from solar-powered cabins to campervans. Its slim design and maintenance-free nature make it easy to install and forget—because it simply works.

With up to 4000+ cycles at full depth of discharge, this battery outlasts most traditional batteries several times over. It handles deep discharge without long-term damage and recharges quickly with solar or AC sources. Whether running fridges, inverters, lighting, or above, the lithium-ion battery 120Ah keeps your gear strong without fluctuation or failure.

What Makes the Lithium Ion Battery 120Ah a Reliable Backup Option

The best part about a lithium ion battery 120Ah is that it does exactly what you need—quietly and reliably.

Retains charge when stored, ready when you need it
Handles frequent cycling without performance fade
Safe for indoor or enclosed use—no gases or leaks
Fast charging speeds reduce downtime during cloudy days
Built-in BMS protects against high/low voltage, current, and temps

From weekend camping to full-time off-grid life, the 120ah lithium-ion battery is designed to provide power you won’t have to second-guess.

Lightweight and Efficient 120 Lithium Battery for Portable Power

When space and weight matter, the 120 lithium battery from Deep Cycle Systems offers an impressive amount of stored energy in a compact form. Whether loading out a caravan, powering a mobile workstation, or backing up an appliance setup, this battery gives you serious flexibility and performance—without the bulk.

Unlike old-style batteries that fade fast or require constant upkeep, this lithium unit holds its voltage even under load and recharges efficiently from solar, mains, or vehicle alternator sources. The 120 lithium battery is practical for anyone needing off-grid power without extra weight or complexity.

Using a 120 Lithium Battery in Everyday Utility and Travel Setups

The compact and reliable 120 lithium battery adapts well to mobile lifestyles and everyday off-grid use.

The lightweight build is ideal for rooftop or under-seat installs
Delivers power to 12V appliances like fridges, lights, or pumps
Supports multiple charge inputs, including solar and DC-DC
Low self-discharge makes it ideal for seasonal use
Long service life reduces replacement costs over time

For travellers, tradies, and off-grid enthusiasts alike, the 120 lithium battery is the gear you install once and count on for years.

Maximise Output with the High-Performance 120 Amp Lithium Battery

Some power systems demand more—the 120 amp lithium battery is built for that. Designed to deliver a high continuous discharge rate, this battery is perfect for energy-hungry tools, large inverters, or systems with high peak loads. It doesn’t just store energy—it’s engineered to release it fast, without sag or stress on your system.

At Deep Cycle Systems, we’ve combined robust cell chemistry with intelligent BMS tech to ensure consistent performance and complete safety. The 120-amp lithium battery is ready to work hard in demanding environments like mobile workshops, marine systems, or industrial equipment.

Applications That Push the Limits of a 120 Amp Lithium Battery

When output matters, a 120 amp lithium battery meets the challenge head-on.

Runs high-surge devices like induction cooktops or air compressors
Maintains voltage under heavy, sustained discharge
Supports multiple charge inputs without overheating
Handles vibration and extreme temps with rugged casing
Perfect for high-output solar and inverter systems

The 120-amp lithium battery delivers serious performance with confidence—perfect for setups that don’t settle for average.

Power Longer with DCS 120Ah Deep Cycle Storage Technology

The DCS 120Ah deep cycle battery is a proven performer regarding renewable energy or backup systems. It’s designed to release consistent energy over long durations, exactly what solar users, off-grid setups, and mobile professionals need. This battery is built to go the distance, whether powering home systems or running equipment in remote locations.

Unlike older battery technology that fades quickly or requires shallow discharges, the 120Ah deep-cycle battery offers true 100% depth of discharge with minimal long-term degradation. That means you can use your energy more often without shortening the battery’s lifespan. With a high-quality LiFePO₄ cell structure and DCS’s active battery management, it’s a smarter, longer-lasting energy solution.

Why a 120Ah Deep Cycle Battery Supports Continuous Energy Use

For users who cycle power daily—solar users, RV travellers, even remote job sites—the 120Ah deep cycle battery keeps things running smoothly.

Delivers consistent energy over long discharge periods
Can be cycled daily without reducing performance
Lightweight, compact design fits into mobile builds
Fast recharge times reduce downtime between uses
Protected by an advanced BMS to manage stress and heat

If your setup relies on dependable, daily power, the 120Ah deep cycle battery is a workhorse you can trust.

Rugged and Smart: The DCS 120Ah Deep Cycle Battery for All Conditions

The DCS 120Ah deep cycle battery combines cutting-edge engineering with real-world durability. Built to withstand heat, vibration, and deep discharge, this battery is ideal for solar systems, marine environments, and mobile installations that require consistent energy. It delivers full power without voltage drop, and thanks to its innovative internal system, it protects itself while providing peak performance.

What makes it stand out is its all-weather capability. Whether mounted in a 4WD engine bay or powering off-grid solar in the bush, the 120Ah deep-cycle battery continues to perform. It doesn’t need ventilation, maintenance, or frequent replacements—just dependable, efficient energy—whenever and wherever you need it.

Where the 120Ah Deep Cycle Battery Fits in Modern Solar Systems

The 120Ah deep cycle battery is designed for systems where uptime and reliability matter most.

Integrates easily with solar charge controllers and inverters
Provides smooth, stable output for sensitive devices
Supports both short-term surges and long-term loads
Ideal for cabins, tiny homes, and mobile setups
Holds charge well in storage with very low self-discharge

From energy independence to remote flexibility, the 120Ah deep cycle battery is one of the most adaptable and dependable in the DCS lineup.

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DOWNLOAD APP (DCS LITHIUM)

DCS Bluetooth Technology powered by DCS Lithium, this APP is only for DCS Lithium batteries which is based on BLE 4.0 technology. Every DCS battery pack comes standard with our detailed battery monitoring via Bluetooth.

This App provides comprehensive monitoring for DCS Lithium batteries, including:

SOC%
Time Remaining
Battery pack voltage, Power & Current
Battery Management MOSFET temperature
Individual Cell Status with balancing indicators.
Connectivity distance up to 10 meters.
Every DCS battery pack comes standard with our detailed battery monitoring via Bluetooth

Learn More About the DCS LITHIUM APP

Click Here to Watch the App Overview Video

Battery Bundles

Sale

12V 120Ah + Victron Smart MPPT 75/15 + Victron Smart 30A dcdc charger

Ultra-Safe

Explosion-proof / No leakage

Stable

Low Internal Resistance / Proven Stability

Long Life

Ultra-long cycle life

Guaranteed A Grade

Contracted A Grade cell supply

12V 120AH Lithium Ion Battery

DCS Battery delivers a minimum of 2500 Cycles
Ideal replacement for Gel or Lead Acid Batteries

Smartsolar Mppt 75/15

Ultra-fast Maximum Power Point Tracking
Load output for prevention of over-discharge of the battery

Victron Smart 30a Dcdc Charger

Dedicated solar regulator
Dedicated dcdc charger
Both fully programmable via Bluetooth
Obtain full 30A from engine + whatever current the solar panels will provide

Availability: In Stock

Sale

Enerdrive Aux Bundle Deal – 12V 120Ah + DC2DC

Ultra-Safe

Explosion-proof / No leakage

Stable

Low Internal Resistance / Proven Stability

Long Life

Ultra-long cycle life

Guaranteed A Grade

Contracted A Grade cell supply

12V 120AH Lithium Ion Battery

DCS Battery delivers a minimum of 2500 Cycles
Ideal replacement for Gel or Lead Acid Batteries
High performance compared to Traditional Batteries

12V 40A DC to DC Battery charger.

Features separate inputs for Engine and Solar Charging
Auto converting from Engine Charging to Solar Charging
40A output up to 40°C that Decreases for Smaller Ah Batteries

Availability: Limited Stock Available, Only While Stock Lasts

Sale

Redarc Aux Bundle Deal – 12V 120Ah + BCDC1250D

Ultra-Safe

Explosion-proof / No leakage

Stable

Low Internal Resistance / Proven Stability

Long Life

Ultra-long cycle life

Guaranteed A Grade

Contracted A Grade cell supply

12V 120AH Lithium Ion Battery

DCS Battery delivers a minimum of 2500 Cycles
Ideal replacement for Gel or Lead Acid Batteries
High performance compared to Traditional Batteries

Redarc BCDC1250D Battery Charger

50amp output makes it the most powerful in REDARC’s BCDC range
Maximises the performance and life of your auxiliary battery

Availability: Limited Stock Available, Only While Stock Lasts

BATTERY TERMINAL CONFIGURATION	LHP – Left Hand Positive, RHP – Right Hand Positive

Battery User Guide

Battery Installation Locations

DCS Batteries that are in a sealed traditional style battery case are IP rated 54 unless otherwise specified.

As there is a considerable amount of electronics inside the battery cases, it is important that these batteries are protected from the ingress of particles and water.

IP54 means that there is partial protection against dust & similar particles & protection against splashing water from any direction for a minimum of 10 minutes.
IP54 MEANS THE BATTERIES ARE NOT WATERPROOF

Our DCS Slimline battery range is IP rated to 53 unless otherwise specified.
IP53 means that there is partial protection against dust & similar particles & protection against splashing water up to 60 degrees from the vertical with limited ingress permitted for 3 minutes.
IP53 MEANS THE BATTERIES ARE NOT WATERPROOF.

DCS batteries should be installed and operated in a location that will not exceed the specified operating temperatures.

Make yourself aware of the new requirements that relate to battery storage, IP ratings and venting. Australian / New Zealand Standards (AS/NZS 3001.2:2022)

Do Not

Install DCS batteries underneath a vehicle or caravan, or any other external location that is exposed to the atmosphere unless it is fully contained inside a suitable battery housing that will prevent the ingress of particles & or water. Also, sufficient mechanical / structural protection is needed to prevent damage from rocks and debris during recreational vehicle travel.
Pressure wash or hose your batteries. You can wipe them down with a damp cloth if needed.
Submerge your batteries in any fluids.
Install DCS batteries near high heat sources, e.g. exhaust manifolds or turbo chargers.

Operating Temperatures

Each battery has a designated operating temperature range depending on the cell type used.
Our under bonnet Hybrid battery range (using cylindrical cells) is designed to work in ambient temperatures between -30°C to 110°C. Do not operate outside of this temperature range.

Our 12V 180Ah auxiliary batteries have an operating temperature range of -30°C to 60°C. The DCS BMS will not allow these batteries to operate if the 60°C is exceeded.

The DCS BMS will not allow a frozen Battery that is below 0 degrees Celsius to be charged. Charge will only be allowed when the ambient temperature of the battery cell is back above 0°C.
Discontinue the use of a battery immediately if the battery becomes excessively warm whilst in a resting/standby state.

Please check the specifications for the recommended operating temperatures of your particular battery on the DCS website.

www.deepcyclesystems.com.au

Securing your battery

Your battery must be secured to prevent movement. Restraints must prevent any movement under a pulling force of twice the battery weight.

The recommended hold-down bracket torque is 4 N-m. or 3.5 lb-ft.

Care has to be taken to prevent the battery lid seal/gasket from deforming when securing the battery, which could affect the IP rating of the battery. Do Not over-tighten the battery holding clamps.

Battery Charging

Use only approved Lithium-Iron Phosphate specific chargers for your battery’s nominal voltage, chemistry and maximum charge rate with the correct charging stage voltages.

All DCS 12V cylindrical cell packs to be charged at:

14.4V Bulk

13.5V Float

The DCS 12V 180ah Auxiliary prismatic cell pack (SKU: DCS-12V-180ah) to be charged at:

14.2V Bulk

13.5V Float

Be aware some chargers have fixed charging voltages and cannot be adjusted.

Check the charger specifications for charging voltage levels & charging profiles before purchasing.

Alternator Charging

Our under-bonnet dual battery systems, 80ah Extreme & Slimline range, can be charged directly from the vehicle’s alternator, providing that they are the only battery chemistry being charged.

For example, you cannot parallel a Lithium battery to a lead acid battery and charge from the alternator.

This type of set up has to be separated by using a DC-DC Charger.

If you are parallel connecting batteries together, they have to be the same chemistry, nominal voltage, capacity and age.

Each battery has a maximum charge current listed in the specifications table that should not be exceeded; otherwise, permanent damage could be done to the battery.

When the batteries are parallel connected together, this doubles the amount of current the batteries can be charged at.

For example, our DCS 180ah (2 x 90ah ) dual battery system. The maximum charge current is 80 Amps per battery. So 2 x 80A = 160 Amps. This means you can charge these batteries provided your alternator’s max. output does not exceed 160Amps.

Before choosing a battery, check the maximum output current your alternator can produce and also find out the Cold Cranking Amps (CCA) needed to start your vehicle.

Your factory alternator is generally the best alternator to use, and there is no need for high output aftermarket alternators.

Check the specifications table on the DCS website for the particular battery you are interested in, and look for Lithium Cranking Amps (LCA).

If the LCA meets or exceeds the CCA for your particular vehicle, then the battery is suitable for your vehicle.

Parallel Connected Batteries

Connect Battery 1 Positive to Battery 2 Positive

Connect Battery 1 Negative to Battery 2 Negative ( This cable is extremely important as some vehicles use the chassis as a negative link, which is prone to failing due to corrosion, which causes a high resistance. )

In Balance Wiring

When you have batteries that are wired in parallel, as described above, it is good practice to wire your loads and inputs in balance.

What this means is, for example, to connect loads & inputs positive to the first battery e.g. Battery 1 and the negative loads & inputs to the last parallel connected battery e.g. Battery 2.

This is important when using an inverter that can have a high current draw so that they evenly draw from the parallel connected batteries.

Storage

If you are not going to be using the battery for some time, charge the battery fully to a 100% state of charge using the correct charging profile and voltages.

Disconnect everything off the battery terminals, and it can be left in this state for up to 3 months.

After 3 months, cycle the battery, fully discharge the battery (11.5 volts), then fully charge the battery, and the battery can then be left in this state for another 3 months.

Do Not

Use a lead acid charger / maintainer on a Lithium battery.

DCS LFP App

Every DCS LFP battery pack comes standard with detailed battery monitoring information via Bluetooth. (BLE 4.0 Technology)

The app can be downloaded to Android or iOS devices that are Bluetooth enabled.

Comprehensive battery monitoring information for DCS LFP batteries include

SOC%. (State Of Charge)
Battery pack voltage, Current & Power
Time Remaining
Individual Cell Voltage Status
Battery Management MOSFET temperature
Connectivity distance up to 10 metres.

Renaming Your Batteries Using The App

Open the DCS LFP app and connect to the battery.
Tap on the three horizontal lines on the top right hand corner of the screen.
Input Password. 736263 > OK
Name ………… > OK
Refresh the battery list by tapping the circular arrow.
Select custom and your battery will now appear in this section.

Modifications

Do not attempt to alter, modify or repair any part of the battery.

Any modifications to the battery will void your warranty.

Fully Discharged Battery

The BMS will emergency open the circuit of the battery terminals to protect the cells. Typically, you will see 3 - 4 volts across the battery terminals when using a multimeter. The BMS needs a 12V supply with at least 1A of current to release and wake up from a cell emergency protection state.

Most mains chargers with a lithium profile will do a slow recovery charge, as will most solar regulators. Some chargers on the market today that are advertised as ‘lithium’ compatible still don’t have the firmware to do a slow recovery charge to release BMSs. If you have a charger that will not wake up the BMS, the easiest way to wake it up is to connect an unregulated solar panel directly to the battery terminals; however, ensure all loads are disconnected before you do this. Having said that, every system should have a suitable low cut-off voltage to shutdown loads/accessories so that the batteries are not fully drained.

“Batteries cannot be left flat/empty; if the low voltage cutoff is triggered, the battery pack should be fully charged as soon as possible. If access to a suitable charger is not possible, disconnect all loads from the battery terminals. The warranty will be void if the battery pack has been left in a low voltage cutoff state for longer than 14 days.”

The most important thing is to isolate everything from the battery terminals, as cables/loads connected to the terminals cause more power drain as the FET gates have to remain closed to cull the accessory standby loads connected to the battery pack + offset BMS standby power consumption.

Incorrect State of Charge Due to a Synchronisation issue:

The state of charge is a calculated value by the BMS and will need to be reset (synchronised) every now and then.

The synchronisation process is automatic and is performed each time the battery is fully charged. The battery monitor (BMS) determines that the battery is fully charged when all 3 "charged" conditions have been met. The "charged" conditions for 12V batteries is:

Charged Voltage (> 14.0 Voltage)

Tail current (4% of battery capacity)

Charge detection time (1 minute)

Electrical Installations Standard ( AS/NZS 3001 . 2 : 2022 ) For Transportable Structures which includes Recreational Vehicles, Caravans etc.

Please note AS/NZS 3001 is made mandatory by electrical legislation in each state and territory.

The new standard includes requirements for “connectable electrical installation batteries” covering any battery that is installed with the primary purpose of supplying the living / accommodation features of a transportable structure, which includes recreational vehicles and caravans etc.

Below is a brief summary of some of the new requirements.

Lithium - Ion Batteries

The location must be appropriate to ensure that the battery operates within the manufacturer’s defined operating temperatures and IP rating.
Batteries must be located in a position that prevents any vented gases from entering a habitable area of the recreational vehicle. Any vented gases have to be vented externally from the vehicle. ventilation openings have a minimum vent area requirement, which is calculated based on the ratings of the battery. Any opening into the interior (habitable area) must be provided with an air seal.
Any metallic service lines (eg. Gas, Diesel, Water etc.) located near the battery must be at least 300mm. clear of the battery terminals or must be shielded with dielectric material to prevent against short circuits.
A battery must be secured to prevent movement. Restraints must prevent any movement under a pulling force of twice the battery weight.

Download PDF

FAQ

CELL SAFETY INFO - Why LiFePO4 (LFP)?

Lithium Ferrophosphate (LFP) is a flame retardant, stable, safe and proven cell chemistry that has a very good energy density around 325 Wh/L. This cell chemistry can be engineered for various applications by adjusting the ratio of elements to provide high performance characteristics. E.g. the DCS marine battery range runs 2C cells, which means our little 75Ah battery will discharge comfortably at 75Ah x 2C = 150A. The DCS 80Ah Extreme runs 10C cells which means the 80A can comfortably discharge at 80Ah x 10C = 800A but is of course limited to lower currents due the the Battery Management System.

LFP also has very good cycling durability between 2,000 ~ 12,000 cycles can be achieved depending on how well the cells are managed, and the lowest rate of capacity loss (aka greater calendar-life) compared to other lithium cell chemistries.

WHY YOU CANNOT USE A VSR BETWEEN TWO DIFFERENT BATTERIES CAPACITIES & CHEMISTRIES?

Battery cells are simply a bunch of resistors with the ability to store energy. A 100Ah battery pack has a different resistance characteristic compared to a 50Ah battery pack, that theoretical difference in resistance is 2:1. So if you connect a 100Ah battery in parallel to a 50Ah battery there is no way for these two batteries to equalise and therefore you can’t charge them correctly. So for example connecting a 60Ah calcium starting battery to a 120Ah AGM via a VSR (Voltage Sensing Relay) you cannot charge both batteries correctly and from that day onwards you are prematurely destroying both battery packs. Same theory applies with lithium’s it’s still a battery pack.

What’s the solution? A DC-DC charger, you now have a permanent point of isolation (meaning that both batteries are never connected to each other in parallel). The DC-DC charger takes the surplus power from battery A (engine) and chargers battery B (aux/house). This device now allows any battery capacity and or chemistry to be used.

What if both batteries are the same, can I run a VSR between exactly the same two batteries?

Yes you can, but lithium’s have a different voltage curve, so you would still need to use a programmable VSR to dial them in correctly. You would also need to ensure the batteries are programmed to never exceed a 10%SOC variance, any larger and you risk damaging the BMS's. These devices also draw a lot of power when engaged to so it’s best to run the two batteries in permanent parallel and run a load disconnect instead of a VSR.

The advantages of the lithium battery cell chemistry

Lithium battery cells have a super low resistance so are very easy to charge and very efficient. This level of efficiency means you can charge them at very high C rates. For example if you look at the charge rate of a 100Ah AGM battery the recommended charging current will be around 25A, which is a 0.25C charge rate. If you consider the DCS 12V 100Ah Lithium battery it can be charged at up to 70A which is a 0.70C charge rate. This means you no longer need to consider DC-DC chargers as you can connect our batteries directly to high power charging devices such as suitable alternators, or large buck boosters. For example our popular dual 90Ah battery system for boats and 4WD vehicles, can be connected to alternators up to 160A.

WHY CAN DCS BATTERIES BE CONNECTED IN PARALLEL WITHOUT ANY EXTERNAL COMMUNICATION SYSTEM?

Because our batteries are internally voltage regulated and because our BMS has such a high sustainable peak discharge current they will do an amazing job of equalising very quickly.

WHAT HAPPENS IF I FULLY DISCHARGE MY BATTERY TO EMPTY?

The BMS will emergency open circuit the battery terminals to protect the cells. This means there is no longer any resistance in the system. The BMS needs a 12V supply with at least 1A of current to release and wakeup from a cell emergency protection state.

Most mains chargers with a lithium profile will do a slow recovery charge as will most solar regulators. Some chargers on the market today that are advertised as ‘lithium’ compatible still don’t have the firmware to do a slow recovery charge to release BMS’s. If you have a charger that will not wakeup the BMS, easiest way to wake it up is to connect a unregulated solar panel directly to the battery terminals, ensure all loads are disconnected before you do this. Having said that every system should have a suitable low cut off voltage to shutdown loads/accessories so that the batteries are not fully drained.

"Batteries cannot be left flat/empty, if the low voltage cutoff is triggered the battery pack should be fully charged as soon as possible. If access to a suitable charger is not possible, disconnect all loads from the battery terminals. The warranty will be void if the battery pack has been left in a low voltage cutoff state for longer than 14 days."

Most important thing is to isolate everything from the battery terminals, as cables/loads connected to the terminals causes more power drain as the FET gates have to remain closed to cull the accessory standby loads connected to the battery pack + offset BMS standby power consumption.

BATTERY MONITOR SETTINGS

Use the following settings:

Charged voltage 14.0V
Tail current 4%
Charged detection time 1min
Peukert 1.05
Charge efficiency 98%
Current threshold 0.1A
C rates: refer to the battery pack capacity

WHAT IS THE BEST STATE/CHARGE TO STORE THESE BATTERIES ?

Fully charge to 100% isolate everything from the terminals and leave for max 3 months and then cycle (fully discharge and fully charge) and leave again for 3 months etc…. Minimum 4 cycles per year to not effect the cells capacity.

WHAT SOC DO MODERN SMART ALTERNATORS TYPICALLY CHARGE BATTERIES TO?

The reason many factory batteries fall over after 9/12 months is because modern/smart alternators typically drop the alternators voltage output to 13.5/13.6V. This voltage is not high enough to charge wet/calcium/lead acid batteries so from the getgo they are destined to fail prematurely. They are typically under charged to around ~80%SOC at these voltages.

So what happens when DCS Hybrid batteries are connected to smart alternators? Exactly the same thing they get charged to around the same 80%SOC. However because LFP has no memory effect that's perfectly fine. By only charging to 80% you are further improving the service life of our batteries. It's no not necessary to charge our batteries over 80%SOC. The only advantage is that you give the BMS a chance to detect full charge voltage and calibrate the SOC readout. So try to plug into mains once a week to fully charge your batteries, especially if your not running any fixed solar supply.

RECOMMENDED CHARGER SETTINGS FOR DCS 12V BATTERIES:

All DCS 12V cylindrical cell packs can be charged as follows:

Bulk: 14.4V
Float: 13.5V

The DCS 12V 180Ah Auxiliary prismatic cell packs (SKU: DCS-12V-180Ah) need to be charged as follows:

Bulk: 14.2V
Float: 13.5V

SOC% Out - How to Reset?

When the battery pack is discharged down to 11.50V the BMS resets to 0%SOC and now is placed in a relearning state - the pack must be fully charged continuously without stopping to calibrate again. Charge it on a mains charger to 14.60V.

Depending on the usage pattern, best to fully cycle the batteries once every 3 months to give the cells a refresh. To fully cycle a 12V pack discharge to 11.50V and charge to 14.60V.

BMS & CMS

Here at DCS, designing lithium batteries is not only our bread and butter, but we love this safe, stable, robust, and high-performance cell chemistry so much that we decided to develop our own range of Battery and Cell Management Systems in 2015.

DCS Battery Management System:

What was the objective? Well, the reason we embarked on this project was that all the basic Chinese designed BMS’s are just protection boards, and it is hard to call them a BMS when they don’t do any cell balancing or provide any means of programmability for various parameters and cell control. A lot of Battery Management Systems that we have tested were using inferior PCB engineering design techniques and poor components. That means continuous performance above 100A was more or less impossible, and reliability was also questionable when pushing above 100A with those Battery Management Systems.

Our key BMS objective was to develop a high-performance 200A BMS that could do;

200A continuous operations using high-quality components
To have a minimal increase in temperature at peak output current (as these circuit boards are installed inside battery packs, limiting internal heat build-up that is crucial for the longevity of the battery cells).
Designed for engine cranking applications, it has to deliver a minimum of 1200LCA’s for 10 seconds (because of the limited voltage drop with suitable lithium cells, it’s very easy to crank over modern engines. Most engines will start in under 1sec, so 10 seconds is plenty). CCA’s don’t apply to lithium batteries as this standard was developed for lead-acid batteries and needed to deliver 30 secs of cranking amps. When a lithium battery is controlled via a BMS, the correct terminology is LCA = Lithium Cranking Amps based on delivering 10 secs of cranking amps.
Suitable for high temperatures applications, e.g. engine compartments. It will be stable up to 180 degrees C.
Bluetooth and WiFi connectivity in order to develop a comprehensive app platform
Pass MIL vibration testing standards (to open up the development of batteries for just about any application).

In a nutshell, the design needed to be tough and reliable for those who use them in the field with no room for error. The construction materials, coating and surfaces, assembly techniques are critical in designing a reliable system. After submitting our brief to all major leading manufacturers in Europe, Japan, USA and Korea, we assessed their expertise and ended up working with a leading and well known Japanese semiconductor manufacturer.

This is a typical Chinese 100A 4S BMS design

This is the DCS 4S 200A BMS

After three years of development, in early 2018, we were satisfied with the circuit board stress testing and released the first batch of our newly developed BMS’s right across our entire 4S (12V) & 16S (48V) battery range. At the same time, we hired an app development team to start working on the software integration to launch our first app platform. The first GEN1 BLE DCS BMS’s that featured Bluetooth chips were launched in OCT 2019. The app platform required a lot of tweaking both on the hardware and software front, and our GEN2 BMS’s were released in mid-2020 along with a more stable app platform with a new design scheme. Our latest GEN3 BLE BMS’s had been released in JAN 2021. The accuracy and stability of the DCS LFP App monitoring system is now very mature and refined. Some additional features had been added along with the ability to create custom battery names. We can produce our DCS BMS technology in any continuous rating range from 10A to 200A with our comprehensive BLE DCS LFP App platform.

DCS Cell Management System:

Having developed such an industry-leading and reliable BMS, it made no sense to combine the cell balancing system together with the BMS. So with our many years of experience in designing and maintaining lithium batteries, we have developed a stand-alone CMS to compliment our BMS. CMS? What? OK, so there are two ‘theories’ of cell balancing in the lithium world passive and active. Passive balancing is a cheap inferior method of cell management as it can burn resistors in an attempt to bleed cell strings. In contrast, active cell balancing is a more complex and efficient balancing technique that redistributes charge between battery cells during the charge and discharge cycles.

Passive balancing has two fundamental setbacks;

Heat: We don’t want unnecessary heat build-up inside a battery pack. The less internal heat, the lesser the impact on the battery cells over time
Resistors have a limited service life, and once they fail game over, you have no cell management. But more importantly, they can fail in such a way in which they will keep drawing power and eventually destroy the cells.

Active balancing is the only way to manage lithium cells correctly. There are many ways to design an integrated circuit (IC) to actively manage cell strings. At DCS, we have tested well over 10 different methods of active balancing IC’s over the years and, in the end, again decided to develop our own active management circuit boards with the best-combined techniques based on our stress testing. Our in house PCB design engineer Max, designed our circuit boards to again meet the following criteria:

High current movement (our latest boards now achieve 3.7A dynamic movement per channel)
Thermal management to ensure the boards remain reliable in harsh environments
Be able to withstand maximum current and thermal loads to ensure long term reliability
Fail-safe design, if any component fails, it won’t compromise the battery pack (not consume power from the battery cells)

This is the DCS 16 channel CMS

There are, of course, some other software features and parameters, which we can’t disclose on this page to the public, as well as some very fancy hardware. But what our latest 04 channel and 16 channel CMS’s do is they can easily manage up to 1000Ah battery banks. So, for example, if you wanted to use our 16 channel CMS’s you could run a 51.2V 1000Ah single battery pack, which would be 51.2kWh in size! The DCS 15kWh batteries are just shy of 300Ah in capacity, so one can only imagine the tight CMS control these batteries are under, and that’s why we back them with a 10 year / 80% capacity warranty.

The DCS 16 channel 59.2A active cell balancing system is so powerful that it will change the battery storage market forever. With this system, the lithium market will continue to dominate for the foreseeable future. Of course, all DCS batteries now feature both our BMS & CMS circuit boards.

We design all our own PCB hardware and the circuit boards are tested to withstand a minimum of 10 years of severe abuse. This video is the MIL-STD 810G Method 514.6 which includes 4 procedures for different modes of vibration.

How to wire batteries correctly

How to Wire Batteries Correctly

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