MIGHTY MAX BATTERY 12V 50AH Replacement Battery for GS Portalac PE12V40 TEV12500 MAX3842524 - The Home Depot
勝特力電子零件材料>TEV12500 GS_免加水電瓶12V,50Ah GS Battery
Spare 12V lead acid battery? I repurposed it into a supersized USB power bank! Also works with car batteries (a basic electronics understanding is required!) : r/recycling
Amazon.com: 12V 50AH Replacement Battery for GS Portalac PE12V40, TEV12500 : Health & Household