LiFePO4 20ah Mini-Battery Box

The design of this battery box came from a decision to not put a 2nd battery in my 4runner and instead make a portable unit much like the Goal Zero. The Goal Zero is a pricey unit and still only gives you an AGM battery for their lower end units. Reverting to a thread on Expedition Portal, I looked into making a LiFePO4 setup for myself. I had at first just bought the batteries, a BMS and a charger, slapped it all together and used that for a short time. With it just being wrapped in tape and partially exposed, I went all out and designed a case for it. It’s incredibly convenient for inflating the air mattress and putting my fridge anywhere I want outside.

Here is what you need to build a unit:

Harbor Freight Apache 1800 sealed box (or equivalent)
12.8V 30A BMS
12.8V 20ah LiFePO4 Battery Pack
Marine Grade Dual USB Socket and Cigarette Lighter Power Socket
Carling Switch
DC 0-30V LED 3-Digital Display Voltage Voltmeter Panel
Tenergy 12.8V/14.6V (4S) 10A LiFePO4 Battery Charger
DC-DC Buck Converter (Adjustable)

3D Models

The panel has a plug for the small 15A Anderson connectors that once wired up, can be glued to the inside of the panel. This gives the access to charge or draw power externally without using the cigarette plug. I plan to model up a water resistant plug eventually to keep dirt and water out if kept outside.