Mobile lab power supply

My neighbor gave me a defective battery from an ebike with only 8 (or six? don't know anymore) defective cells and I decided to make a mobile lab power supply with USB charging capabilities. It is configured to 6S7P with 18650 Li-Ion bateries. It has roughly 14Ah and 25,2V fully charged. Inside it is a little messy, but it works great.

The hardware is from one DC-DC step-down regulator (LM2596) with LED display, wich shows the input voltage from the battery. A combined module for volt and am