Just as a friendly warning to any newbies out there thinking that it's safer to use a spot welder. It isn't necessarily. The heat that can cause the battery to go, but so can piercing the casing and allowing oxygen in. Over volt the spot welder or linger on the tab for too long and it can over heat or melt the casing. If it does, the case ruptures and it starts a lithium fire. Fire extinguishers won't do a whole lot of good for a lithium fire until the lithium has reacted off. So have a bucket of sand handy to dump it in.
The advantage of the spot welder is that - if you know how to use it - there is far less lingering time compared to solder.
Go to 1:45 if you want to see what it looks like.
What I'm saying here is: be careful and I strongly recommend eye protection.
So I agree whole heartedly with fantablium. If you want to try it. Get pre-tabbed cells and solder the tab. Don't try and save the 50p for the un-tabbed ones.
Warning aside. This is well worth doing on any device. For those who do not understand. You can safely put any amperage
(mAh
) cells into the device, but the voltage
must be the same. Higher amperage is what allowed fantablium to go from the 9 hours original life to 15+ hours.