12V 400Ah lithium iron phosphate deep cycle battery. 5120Wh high-capacity energy storage for demanding RV, marine and off-grid applications.
Product Overview
The 12V 400Ah LiFePO4 battery delivers 5120Wh of deep-cycle energy in a single unit built for extended off-grid autonomy. Designed for large RVs, liveaboard boats, and off-grid cabins that need multiple days of power without recharging, it replaces four 12V 100Ah lead-acid batteries with a fraction of the weight and far more usable capacity.
For distributors and installers serving the premium RV and marine market, this battery covers the top end of the 12V range. See also our 12V 300Ah model and 12V 200Ah model for smaller options in the same family.
- 5120Wh usable energy — multi-day autonomy for large RVs and boats
- 250A continuous BMS — handles high-draw inverters up to 3kW
- Deep-cycle LiFePO4 — thousands of cycles, 10x lead-acid lifespan
- Expandable — parallel up to 4 units for 20kWh+ systems
Technical Specifications
| Group | Parameter | Value | Status |
|---|---|---|---|
| Electrical | Nominal voltage | 12.8V | Typical |
| Electrical | Rated capacity | 400Ah | Typical |
| Electrical | Energy | 5120Wh | Typical |
| Electrical | Cell chemistry | LiFePO4 | Typical |
| BMS | Continuous discharge | 250A | Typical |
| BMS | Protections | Overcharge, over-discharge, over-current, short-circuit, temperature | Typical |
| Physical | Dimensions | To be confirmed | To Be Confirmed |
| Physical | Weight | Approx. 38-42 kg | To Be Confirmed |
| Environmental | Operating temperature | Charge 0-55C / Discharge -20-60C | Typical |
Reference values. Final specifications confirmed in formal quotation.
Applications
- Large RV and motorhome house systems
- Liveaboard sailboats and trawlers
- Off-grid cabins and tiny homes
- Mobile workshops and food trucks
Wholesale, OEM & ODM
We are not limited to listed SKUs. Capacity, BMS, housing, and features customizable through our manufacturing partners. Request a Quote
Frequently Asked Questions
How many days of power does 5120Wh provide?
Depends on daily consumption. At 1.5kWh/day (typical efficient RV), about 3 days. At 3kWh/day, about 1.5 days.
Can I parallel multiple units?
Yes, up to 4 in parallel for 1600Ah total. Use identical units at equal voltage.

