Replacing the old battery on rechargeable bike lights

The author shares their experience of replacing the old battery on their rechargeable bike lights, providing a step-by-step guide. They use a replacement battery from a hardware store and a soldering iron to remove the old battery from the light's casing. The replacement process involves removing the old battery, cleaning the contacts, and installing the new battery. The author notes that the process is relatively simple and requires minimal tools. The replacement battery has a 1.2V 1000mAh capacity, which is a significant upgrade from the original 0.7V 500mAh battery.