Electronics and lighting

LiFePO4

Also called lithium iron phosphate, LFP battery, lithium iron phosphate battery

What is a LiFePO4 battery?

Lithium iron phosphate, the lithium chemistry used in most 12 V drop-in batteries: lighter than lead-acid, with steadier voltage as it drains.

LiFePO4 is a lithium battery chemistry built around iron phosphate. A 12 V LiFePO4 battery is four cells in series with a nominal 12.8 V, and most are sold as drop-in replacements for sealed lead-acid batteries of the same size, with the same kind of terminals.

For anglers the practical differences are weight and voltage. A LiFePO4 battery weighs much less than lead-acid of the same amp-hours, and it holds its voltage close to steady until it is nearly empty, where a lead-acid battery sags the whole way down. Electronics that shut off at a voltage floor get more of the battery's capacity as a result.

The trade-offs are cost and charging. LiFePO4 costs more up front, needs a charger with a LiFePO4 profile to fill properly, and most makers warn against charging it below freezing. A built-in battery management system, or BMS, protects the cells from overcharge, over-discharge and short circuits.

In practice

If you carry a battery down a bank or into a kayak, the weight saving is the reason to pay for LiFePO4. Buy the matching charger at the same time.

Common questions

Can I charge a LiFePO4 battery with a lead-acid charger?

Use a charger with a LiFePO4 setting. Several battery makers note that an automatic lead-acid charger may stop early and leave a lithium battery short of full.

Where this comes up

The guides that use lifepo4 and show it on real gear.

Last reviewed . LiFePO4 is one of 224 terms in the fishing glossary.