Custom Lithium has unveiled its all-new Ultra Slim XL Series, the largest single 12V lithium batteries currently available in Australia.

Available in 800Ah, 920Ah, 1120Ah and 1250Ah configurations, the Ultra Slim XL Series is aimed at serious power users running energy-hungry setups in 4×4 canopies, caravans, campers and off-grid systems. Each unit delivers massive storage capacity in a compact, mount-anywhere format, reducing the need for multiple battery banks.

When it comes to caravans, big canopy builds, or fully equipped American truck setups, having this kind of power means longer run times without the need to recharge. It also opens the door to running high-draw luxuries such as coffee machines, air fryers, induction cooktops or fridges with ease – making life off-grid more comfortable and self-sufficient, no matter how remote the destination.

In fact, Kedron Caravans has recently partnered up with Custom Lithium, utilising its XL range of batteries for off-grid living. Kedron already have a few units out in the wild and are in the process of installing more.

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Each model features dual terminal outputs to keep wiring clean and balanced – ideal for separating inverter loads from general 12V accessories. A 380A continuous discharge BMS with 1800A protection shutdown provides serious current-handling capability, while reinforced mounting and improved thermal efficiency ensure durability in harsh Australian conditions.

“Over the past year, we kept hearing the same thing, ‘Give me more power.’ So, we did. We built it, tested it, and now it’s ready,” said Cam, Customer Service & Sales Manager at Custom Lithium.

Custom Lithium, a family-owned company from Brendale, Queensland, makes Australian-made lithium batteries built for tough touring conditions. Its range includes 12V Ultra Slim, Slim, and Compact batteries (100–310 Ah), high-capacity caravan/RV batteries (400–620 Ah), 24V/48V system batteries, plus vehicle-specific kits and accessories.

Beyond gear, the company supports local clubs and community projects, reflecting the family values and mateship central to the 4×4 lifestyle. Choosing Custom Lithium means reliable off-grid power and backing a business that prioritises both performance and community.

The Ultra Slim XL Series continues Custom Lithium’s focus on delivering large-scale, Australian-built energy storage solutions that meet the demands of both recreational and commercial users.

Ultra Slim XL Series models:

  • 800Ah Ultra Slim XL
  • 920Ah Ultra Slim XL
  • 1120Ah Ultra Slim XL
  • 1250Ah Ultra Slim XL

The new range is available now through Custom Lithium dealers nationwide.

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