The 12V 25Ah LiFePO4 battery is a 12.8-volt block of 320 watt-hours on M5 terminals. It bridges the small-battery range and the deep-cycle range, large enough for a modest off-grid system or a full day of portable power, and still a compact single-hand block.
Small Solar
An evening on 320 watt-hours
A shed, a cabin, a boat cuddy or a remote sensor cluster often needs a small 12V system rather than a full house bank, and 320 watt-hours is the size that fits. Work the evening load through: 20 watts of LED lighting for four hours is 80 watt-hours, a phone and a laptop charged is another 60, a small water pump run in bursts adds perhaps 50. That is 190 watt-hours against a 320-watt-hour pack, which leaves reserve for the overnight standby load and a cloudy morning before the panel catches up.
The Refill
Panel and parallel
A solar panel of 100 watts or so replaces that daily draw over a day of decent sun, through a controller set to an LFP profile. When the load grows past what one block holds, two in parallel give 640 watt-hours in the same footprint class; match them by resting voltage first so they share current from the first cycle.
Service Life
Why lithium here
At about 2.8 kilograms this block is a third the weight of the lead battery of the same capacity, and it gives more than 3,000 cycles against a few hundred. On a system that cycles every day, that difference is a battery that lasts the life of the installation against one changed every couple of years, and there is no periodic top-up charge to keep a shelved lead battery from sulfating.
Cold Box
Running a 12V fridge
A 12-volt compressor fridge is the load that decides a small off-grid box. A portable cooler of the Dometic CFX3 class uses on the order of 40 amp-hours a day in warm weather, close to 490 watt-hours, so a single 320-watt-hour block runs it through the warm part of a day and a paralleled pair carries it overnight. Behind a 100-watt panel, that pair holds a camp fridge cold across a weekend without a generator.
Data
Datasheet
| Model | DC12-25 |
|---|---|
| Nominal voltage | 12.8V |
| Capacity | 25Ah |
| Energy | 320Wh |
| Charge voltage | 14.6V |
| Discharge cutoff | 10V |
| Continuous discharge | 25A |
| Peak discharge | 50A (5s) |
| Cycle life | ≥3,000 cycles |
| Weight | ≈2.8 kg |
| Dimensions | 181 × 77 × 167 mm |
| Terminals | M5 bolt |
| Operating temperature | Discharge -20~60°C / Charge 0~45°C |
| Certification | UN38.3 / CE / FCC / RoHS |
Fit
Fitment and charging
The M5 terminals take ring lugs torqued to the datasheet figure, and the case is compact for the capacity. Charge at 14.6 volts from a lithium charger, and set a solar controller to an LFP profile with no equalization. Its BMS covers overcharge, over-discharge, overcurrent, short circuit and a low-temperature charge cutoff, it works from minus twenty to sixty degrees on discharge, and it keeps best in storage at 30 to 50 percent charge.
Reviews
There are no reviews yet.