LiFePO4 vs AGM Batteries for Overlanding

AGM batteries

AGM batteries are sealed lead-acid batteries. They are reliable, familiar, and generally less expensive up front. They tolerate cold better than many lithium batteries and can be a reasonable budget choice.

The tradeoff is weight, slower charging, shorter cycle life, and lower usable capacity. Many AGM systems are planned around roughly half the rated capacity to avoid shortening battery life.

LiFePO4 batteries

LiFePO4 batteries are much lighter for the usable energy they provide. They maintain voltage well under load, charge efficiently, and often allow deep discharge when managed by a quality battery management system.

The main drawbacks are higher initial cost and cold-weather charging rules. Many lithium batteries should not be charged below freezing unless they include low-temperature protection or internal heating.

Usable energy comparison

Recommendation

If you are building a new battery box, truck bed power system, or dual battery system, LiFePO4 is usually the better long-term platform. AGM can still make sense for budget builds, cold-weather simplicity, or systems that already exist.