For 4×4 and off-grid enthusiasts, the Next Generation Ultra Slim series from Custom Lithium takes compact, high-capacity lithium batteries to the next level. 

Building on the standard Ultra Slim range, these batteries are designed for improved performance, higher energy capacity, and enhanced durability in harsh off-road conditions.

The Next Generation Ultra Slim line-up covers a broad range of capacities, including 100 Ah, 200 Ah, 230 Ah, 280 Ah, 310 Ah, 400 Ah, 460 Ah, 560 Ah, and 620 Ah, providing options for everything from short weekend trips to extended overland journeys. Compared with the original Ultra Slim series, the next generation models offer higher usable energy, more consistent voltage output, and increased maximum continuous discharge, making them better suited for 4WDs, camper trailers, and off-grid systems running multiple appliances.

These batteries use upgraded LiFePO₄ cells with refined chemistry for longer life and enhanced thermal stability. Each unit also includes an advanced Battery Management System (BMS) with improved safety features, ensuring protection against overcharging, over-discharging, and overheating even under heavy off-grid loads.

The slim, compact form factor remains a key advantage, allowing installation in tight spaces such as under seats, in canopy compartments, or behind storage panels, while still delivering more power than the original Ultra Slim range. This makes them ideal for fridges, lights, water pumps, winches, and other essential off-road accessories without compromising payload or vehicle layout.

For serious overlanders and off-road travellers, the Next Generation Ultra Slim series offers higher performance, more capacity, and improved reliability compared with the standard Ultra Slim batteries, making it a practical upgrade for any 4×4 or camping setup.

More info at Custom Lithium