Learn how to build a solar-powered 6 AA NiMH battery charger –
Battery Charging NiMH
The Best Rechargeable Battery Charger (for AA and AAA Batteries) | Reviews by Wirecutter
NiMH AA Power Pack | Reconyx
Amazon.com: POWXS AA Rechargeable Batteries with Charger, 2800mAh High Capacity Ni-MH Double A Batteries (8 Pack) and 8-Bay Pro AA AAA Battery Charger with Type-C Fast Charging, Independent Slot : Electronics
Rapid Travel Charger with 4x AA NiMH Rechargeable Batteries - Ultimaxx