Enerwatt WPL31, 12V deep cycle Lithium-ion battery, 100 Ah, 2500+ cycles, group 31, 3 years warranty
As economical as lithium-ion batteries get! The Enerwatt WPL31 is a 12 Volt 100 Ah LiFePO4 battery. The dimensions are such that it fits a group 31 space. These batteries are just 1/3 of the weight of an equivalent lead-acid battery, and they last thousands of cycles. This makes them a great alternative for lead-acid batteries in motor homes, RVs, and boats! Enerwatt is a Canadian brand, and warranty is with a Canadian company.
Also see our Finding Happiness with Lithium-Ion article, explaining the care and feeding of these batteries.
The Enerwatt WPL31 lithium-ion battery is a true deep-cycle batteries, it can repeatedly be discharged a full 100% without damage. The battery has a build-in battery management system (BMS). The BMS allows them to be charged with regular solar PV charge controllers, with the same settings as for any other sealed battery (such as AGM batteries). The BMS also takes care of protecting the batteries from over- and under-charge, low Voltage disconnect, over-current, and automatic balancing of the cells.
Charge settings for Enerwatt LiFePO4 batteries:
- Bulk/absorb = 14.2 – 14.6 Volt, with 14.4 Volt ideal
- Absorb time = about two hours, or until the current drops to 5A or less.
- Float = not needed, set to 13.6 Volt or less
- No equalize, or set to 14.4 Volt if it can’t be disabled
- No temperature compensation, set to 0
- A charge rate of up to 50A is possible
- Battery has to be warmer than 0 Centigrade (32F), or the BMS will not allow charging, discharge works fine up to -20C (-4F)
The maximum discharge rate is 50 Amp continuous, 100 Amp for 10 seconds.
These Enerwatt batteries are meant for a 12 Volt system only! They cannot be connected in series to increase the battery bank Voltage, the BMS is not designed to handle this. They can be connected in parallel to increase the Ah rating. Parallel strings of batteries will increase the charge and discharge rates (i.e. 100A for two parallel strings etc.). Ask us if you have any questions about properly sizing a battery bank.
The manufacturer recommends no more than 3 batteries in parallel. Which will make a 12V 300Ah battery bank.
Enerwatt WPL31 batteries use LiFePO4 chemistry (Lithium-Iron-Phosphate). This is very stable and is not sensitive to spontaneous combustion, in comparison to laptop and cell-phone lithium-ion batteries (which use Lithium-Cobalt-Phosphate chemistry). These are very safe batteries!
Because lithium-ion batteries can be discharged to 100% DOD, and this can be done for more cycles, a smaller battery bank can suffice vs. lead-acid. Since there is no off-gassing these batteries can be mounted indoors.
- Zero maintenance!
- No memory effect
- Compatible with standard charge controllers
- 12 Volt, 100 Amp hour @ 20 hr discharge rate
- Only 1/3 weight of lead-acid & small footprint!
- Dimensions very close to group 31 battery size
- Very low self-discharge rate, holds charge up to 1 year
- Can be mounted in any orientation, zero off-gassing, no dangerous acid
- Active cell management through included battery management system (BMS)
- Long lifespan, true deep-cycle: 2500 cycles at 100% DOD, more if discharged less
- 3 years warranty