Power bank uses 4x AA batteries. Battery: 4x AA batteries (Not included). Suitable for charging other devices like bicycle light, USB fan, USB light, etc. Cable connector: USB Type A female. Aluminium alloy shell.
eBay
AA Battery Holder 6V For 4 x AA Battery Back To Back Holder Case Box Storage With Wire Leads For 4 * AA Batteries Battery case
Aliexpress UK
Waterproof battery holder suitable for use with 2 x AA batteries, the holder features tail leads and IP65 protection level. Holds 2 AA batteries. Features On-Off switch. 150mm tail leads. IP65 protection level.
eBay
Battery Holder 21700 /18650 Case Storage Box Container IP67 Waterproof Battery Case For 18650/ 21700/ AA/ AAA/ Coin Batteries
Aliexpress UK
Battery Sizes Accepted AA. Integrated on/off switch. Robust design with detachable lid and screw closure to maintain seal.
eBay
2 Pack AA/14500 Battery Holder Case for 16 x AA/14500 Batteries Waterproof Plastic Battery Organizer Container Holder 2 Colors
Aliexpress UK
Battery Sizes Accepted AA. Integrated on/off switch. Robust design with detachable lid and screw closure to maintain seal.
eBay
JJC Multi Slots Battery Case for 18650/ AA/ AAA Batteries Waterproof 18650 Case Storage Box Container Holder with AA AAA Tester
Aliexpress UK
Side-by-side WATERPROOF Battery Holders for 2x/4xAA Batteries with Cover and Switch. Waterproof case & switch (IP65). Both include 4x screws for water-tight protection. Airsoft Batteries. Sealed Lead-Acid Batteries.
eBay
Portable 53Pcs Waterproof Battery Organizer Storage Case Bag For 18650 AA AAA 9V Battery Garage Container Box Holder for Battery
Aliexpress UK
AA Rugged Battery Box Container. The battery storage case can hold a total of 8 AA batteries. Ideal for travelling and fit nicely into a rucksack or bag, the boxes are as low profile as possible to keep everything compact.
eBay
For AAA/AA/18650 10 Slots Battery Storage Box Battery Container Clear Hard Plastic Battery Case Waterproof Durable Organizer
Aliexpress UK
Battery Sizes Accepted AA. Integrated on/off switch. Robust design with detachable lid and screw closure to maintain seal.
eBay
Waterproof Bag Battery Safe Bag Anti Dust Weather Resistance Carrying Storage Bag Protective Pouch For Camera Battery AA Battery
Aliexpress UK
For 2pcs 18650 or 4pcs 16340, 72x44x24mm/2.83x1.77x0.88"(not for 18650 whose height exceeds 68mm ) For 2pcs 18650, 76x44x24mm/2.83x1.77x0.88"(not for 18650 whose height exceeds 71mm ). For 1pc 18650, About 75x23x23mm/2.95x0.90x0.90"(not for 18650 whose height exceeds 70mm ).
eBay
Battery Storage Organizer AA & AAA Combo Small Battery Keeper Wall Holder Battery Dispenser Container For 10AAA & 10AA Batteries
Aliexpress UK