Replaced PS3 controller battery with old cell phone battery to avoid buying new controller. Should I be worried? It's not pretty, but it seems to work fine takes a charge again! :
Powertrust 1800mah Lip1359 Battery For Sony Playstation 3 Ps3 Dualshock 3 Wireless Controller Cechzc2e, Cechzc2u With Tools - Batteries - AliExpress
VHBW Battery for Sony PS3 Dualshock 3 Sixaxis Controller, 950mAh - OnlineShop AccuShop.at
Battery 3.7V Li-ion battery for wireless controller Dualshock 3 Playstation 3 LIP1359, LIP1472
How to Charge a PS3 Controller: 10 Steps (with Pictures) - wikiHow
Replacement battery for Sony Dualshock 3, Wireless Controller, CECHZC2E: Amazon.co.uk: Electronics & Photo
Amazon.com: MPF Products 570mAh LIP1359 Battery Replacement Compatible with Sony Playstation 3 PS3 Dualshock 3 Wireless Controller CECHZC2E, CECHZC2U with Installation Tools : Video Games
Amazon.com: Starnovo 1250mAh 3.7V LIP1472 LIP1859 Replacement Battery for Sony PS3 Playstation 3 Dualshock 3 SIXAXIS Wireless Controller, CECHZC2E, CECHZC2U : Video Games