Slim Lithium Battery

$1,090.00$1,990.00 inc. GST

Enhance your vehicle’s utility with our Slim Lithium Batteries, available in 100Ah and 200Ah capacities. Tailored for the tight spaces of 4x4s, utes, vans, and canopies, these slim yet powerful batteries are perfect for powering both 12V equipment and inverters for AC-240V power. Built to withstand the harsh Australian terrain, they deliver high capacity and performance, meeting all your auxiliary battery needs.

Power your tools, lights or essential gear with our Slim designed Lithium Batteries.

SKU: N/A Categories: ,



Power Outlet
Coffee Machine
Cooking Utilities

Australian Made

Made in Brisbane, you can depend on our top-notch quality and rugged performance.

Designed by Enthusiasts

Designed by our team of off-roading and camping enthusiasts, our auxiliary battery systems are perfect to power your adventure.


Continuous BMS AMPs
180 AMP 200 AMP
Standard and Max Charge Current
100Ah model 50AMP Standard, 100AMP Max
200Ah model 100AMP Standard, 200AMP Max
Discharge Overcurrent Protection
100Ah model 750 AMP
200Ah model 850 AMP
Dimensions (mm)
100Ah model 290 x 110 x 200
200Ah model 450 x 120 x 245
Weight (Kg)
100Ah model 8 kg
200Ah model 18 kg
Operating Temp
-20°C – 60°C All size capacities
M8 terminals All size capacities
Charge Voltage
14.2v – 14.6v All size capacities
13.4v – 13.6v All size capacities
Cut off voltage
10.5v All size capacities



Equip your vehicle with a Slim design battery from Custom Lithium. Designed to fit anywhere and deliver the highest battery capacity to power all your gear for longer.


Is it possible to directly replace my AGM battery with a Slim Lithium Battery?

The possibility of directly replacing your AGM battery with our Slim Lithium Battery primarily depends on your charger, as AGM and lithium batteries operate under different charging cycles and chemistries. Lithium batteries, being lighter, more efficient, and boasting a longer lifespan, require more precise charging parameters to prevent overcharging and mitigate potential safety risks.

Before you swap out your AGM battery for a lithium one, it’s crucial to verify that your existing charging system and equipment are compatible with lithium batteries. Please check your equipment manuals thoroughly for lithium support, especially your DC-DC charger, solar charge controller, and 240V charger. This ensures a safe and efficient transition to one of our Slim design lithium auxiliary batteries.

How do I restart a flat Custom Lithium Slim Lithium Battery?

Restarting your Slim Lithium Battery after it runs flat can be done in two main ways:

Method 1: The simplest method involves using a lithium-compatible 240V charger that features a ‘power supply’ mode. To restart the battery:

  1. Connect your Slim Lithium Battery to the 240V charger.
  2. Set the charger to ‘power supply’ mode.
  3. Allow the battery to charge continuously until fully powered.

Method 2: If a 240V charger is not available, you can restart your battery using another 12V battery with similar voltage and capacity:

  1. Position the Slim Lithium Battery next to the other 12V battery, ensuring the terminals do not touch.
  2. Connect the positive clamp of jumper leads to the positive terminal of both batteries.
  3. Connect the negative clamp to the negative terminal of both batteries.
  4. Activate the power source or vehicle equipped with a DC-DC charger to begin charging.
  5. Monitor the charging process, and once charging is confirmed, disconnect the jumper leads starting with the negative clamp.

Note: If your Slim Lithium Battery has been left discharged for an extended period and these methods do not work, it may need to be returned to Custom Lithium for servicing. After successfully restarting the battery, it is highly recommended to charge it to full capacity to ensure optimal performance.

What size DCDC charger would I need for my Lithium Battery?

All the DC-DC chargers we offer are fully compatible with our Slim Lithium Batteries. Depending on your setup, some chargers feature MPPT solar regulators for enhanced solar charging efficiency, while others provide straightforward DC-DC charging.

Choosing the right charger size typically depends on your desired charging speed and the capacity of your battery. Our Slim Lithium Batteries come in just 2 sizes, 100Ah & 200Ah, and we recommend a Victron DC-DC 30A or REDARC Core 40A charger.

If you opt for a charger from a third party or plan to use an existing charger, make sure it is suitable for lithium batteries. It should support a bulk charge setting of 14.2 ~ 14.6 volts and an absorption/float charge of 13.4 ~ 13.6 volts to ensure efficient and safe charging of your Slim Lithium Battery.

What 12v Charge Profiles required for the Slim Lithium Battery?

For optimal performance and longevity, the Slim Lithium Battery requires specific charging parameters. Set your charger to deliver a charge voltage between 14.2v and 14.6v during the bulk charging phase. Once the battery is nearly full, adjust the absorption/float voltage to between 13.4v and 13.6v to maintain the charge without overcharging.

For the 100Ah model, use a charger that can provide a standard charge current of 50AMP and can handle bursts up to 100AMP. For our Slim 200Ah, the charger should offer a standard charge current of 100AMP with the capability to go up to 200AMP for maximum efficiency.

Additionally, if your charger, such as the Victron 12-12/30, includes a LiFePO4 setting, please select this option to ensure that the battery charges correctly according to its lithium iron phosphate chemistry. The cut-off voltage for all models is set at 10.5v to protect the battery from deep discharge.

Additional information

Weight 8 kg
Dimensions 390 × 110 × 200 mm
Capacity Size

100Ah Slim, 200Ah Slim