| | Re: Warranty replacement of CS-2 battery; aftermarket manufacturers?
I would not buy a cheap, knock off battery. You depend on that battery for power when you are away from a power source. Why go for something cheap that probably won't last and could damage your device.
Get an OEM battery made for your specific BB. And never let it run down to less than 20 % if you can help it. I find the battery works best when kept toped up when you are near a power source.