This battery box can store up to 600Wh of energy and features an inverter to convert the 12V DC from the battery to 220v AC to power home appliances. It also features a USB port on the side for charging a phone and a wireless charger on the top of the case.

The battery is made of 90 18650 cells salvaged from broken laptop batteries. Since not all the cells have the same capacity, the packs need to be balanced. I'm using a 3S BMS for this task.
The battery can be recharged using an off the shelf LiPo charger or combined with a solar panel for off-grid usage.

The box also features a 2A USB charger as well as a QI wireless charger. The integrated display shows the battery voltage as well as the power consumption.