Thread: Battery packs

I have a makita drill battery that would be at least 10 /12 years old.Packed it in a month or so ago.Read somewhere in this forum about freezing a batt. so gave it a go. I left it in the freezer for four days then gave it a charge,Tried it in the drill and it worked but only so so.put it back in the freezer for a day and tried again. Have used it for about say six hours of work and it is still going strong on the last charge.Give it a try, noting to loose

I've done it... Did it to a Bosch drill that had gone bung, but it turned out to be a dead drill So I repacked my Ryobi instead

*Most* cordless drills use 1.2V Sub-C type batteries [EDIT: you need the ones with the tabs on them], available from Jaycar. I bought 2.7Ah Ni-Mh cells, which ran to about $6-7 each back then (maybe 2 years ago). Expensive for 12V, even more so for a bigger drill. The advantage was that I went from maybe 0.7Ah to 2.7Ah on the Ryobi - the thing keeps going all day. And the next

The major gotcha apart from being bloody careful soldering batteries together (you really don't want to heat the batteries up) is that a Ni-Cad charger can't charge Ni-Mh batteries. The reason that I was told is that Ni-Mh batteries are pulse charged (short 0.5-or-so second pulses of electricity - I verified it with my multi-meter). So you'll need a new charger if you go that route, unless your current battery is Ni-Mh too. You can always buy Ni-Cad cells if that's your wish.

Cheers,
Dave

Originally Posted by billym

I have a makita drill battery that would be at least 10 /12 years old.Packed it in a month or so ago.Read somewhere in this forum about freezing a batt. so gave it a go. I left it in the freezer for four days then gave it a charge,Tried it in the drill and it worked but only so so.put it back in the freezer for a day and tried again. Have used it for about say six hours of work and it is still going strong on the last charge.Give it a try, noting to loose

OK, I now have a battery taking up space in the freezer.
When I remove it from the freezer, how long should I leave it before charging?
Should it be allowed to thaw, or should it still be cold when charged?

G'day john. I left mine to thaw as I was worried the perspiration might short or affect the charger. Lets know how you go. billym

Thanks billym - we will see how it goes.