20 Pack Exell AA 1.2V 1000mAh NiCD Rechargeable Batteries with Tabs - Perfect for Medical Instruments, Electric Razors, Toothbrushes, RC Devices & Power Tools - Long Lasting Power Supply for Home & Professional Use

I am repairing a rechargeable battery pack for a radio and needed the tabbed cells.I rebuilt the battery pack from my ancient HP 55 calculator using three of these cells. They're working great, no issues at all, though I've only charged them a couple of times so far. It's nice to have the calculator running on battery again, the old worn out pack was giving me about 1 minute of operation after a 12 hour charge. These new cells should run the calculator for more than 7 hours if they are truly 1000mAH as they claim.The cells arrive with some charge in them, maybe close to fully charged. That made me a bit nervous about inadvertently shorting them out during the build process (NiCd's are very powerful) so I discharged them all the way down by temporarily soldering a 10 ohm resistor across each one and waiting 12 hours. You can't do that to Lithium cells but NiCd cells are fine with it. Just discharge each cell individually, never discharge a multi cell NiCd battery pack to 0 (you'll reverse one or more of the cells, causing damage).Another advantage to discharging the cells before assembling is minimizing charge imbalance in the pack - all three cells start out at an identical state of charge (i.e. 0), which is important when you have cells wired in series.As is always the case with welded tabs, you have to be gentle or you can rip them right off - the spot welds are fragile. If you tape the cells together in the proper orientation before you start soldering, you'll have fewer "AUGGHH!" moments where you drop one and it's dangling by its tab.....The only problem is these 1000mAH cells have more capacity, maybe double, than the originals that came with the calculator in the 1970s. That means the charger is going to take about a day to charge them up from empty (the HP charger puts out 50mA constant current). And I'm already putting together another pack, using three NiMH cells (2500mAH!) which will take more than 50 hours to recharge! So my next project is a fast charger using an LTC4060 smart battery charger IC, which will cut the charge time by 90% (and cut off when fully charged, avoiding extended trickle charging which NiMH cells don't like).Bottom line, I'm very happy with these cells so far. I'll post an update if anything goes wrong.So I ordered these batteries for my wireless mouse and battery powered puck lights, unfortunately, these batteries are meant for DIY projects because they come with soldered on tabs. So when I tried plugging them into my battery charging station only 3 of them worked, and it seems like the only reason why they didn't work is because they have the tabs instead of the button endings.Regardless, I was contacted by their customer service guy (Mark) and organized to have these batteries returned with the button batteries sent in exchange, very polite and respectful, problem was resolved in less than 5 minutes this morning.So while I can't vouch for the batteries here, I can definitely vouch for the company in finding you what batteries suite your needs!