There’s a ton of devices out there that have batteries in them but most people never think about it. That’s because they use rechargeables that are sealed inside and topped off with external chargers.

My Ryobi One battery packs are toast and Batteries Plus wants $70 each to rebuild them. I can buy new packs from a big box outlet for ~$35 each or rebuild the ones I have. I've found Sanyo AA 1100 mAh ...