Sure thing, grab the old batteries, strip off the casing, and just solder the terminals to a cheap USB breakout board. Hook that up to a little 3.7V Li‑ion charger circuit and bam—your own DIY power bank. Or if you’re feeling dramatic, repurpose a broken phone charger, swap the cable for a USB-C, and you’ve got a portable juice box for your future zombie apocalypse. Just keep an eye on the voltage, don’t let it overheat, and you’re golden.