Dead rechargeable batteries on cordless drill

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9,283
Location
Fayetteville, NC
Thread starter
It's a Hitachi cordless drill and neither battery would recharge. No charging indicator on the in-wall charger. They have been sitting unused for a while. I have seen videos of people charging a dead battery with ANOTHER working battery but in my case BOTH are dead and won't recharge... Can I use a NOCO trickle charger to charge/boost them? (+ to+ and - to -) . Any danger in doing that?
 

JC1

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4,499
Location
Oshawa, Ontario Canada
How old is the drill? What type of batteries are in the Drill? I wouldn't bother trying to get it recharged. Time to invest in something newer and better. Ni-mh batteries last a long time now. I've got Dewalt 20v batteries that I've been using since 2011. Never an issue even if I leave them for months at a time.
 
Messages
242
Location
Hedgesville, WV
Do you have access to another charger. Even if the batteries are dead you should get some kind of indicator on the charger. I dont have Hitachi but my charger has a blink pattern that indicates the status of the battery.
 

JC1

Messages
4,499
Location
Oshawa, Ontario Canada
Originally Posted by Snagglefoot
To be honest Ni-mh are old technology. It's Lithium Ion now. smile
My bad. Thanks Snagglefoot for the correction! Had a brain f-a-r-t. Lithium Ion are the batteries and yes that's the way to go. You can even get adapters to use on brand of battery on another tool. I'm able to use the Dewalt 20v batteries on Ryobi 18v tools and on Milwaukee 18V tools.
 
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Messages
1,627
Location
Cincinnati, USA
Even Li-Ion has been around long enough that people could have dead, older batteries. If it's Li-Ion, you need to be certain that you do not overly charge them with the trickle charger since it doesn't know when to terminate charge for these. Overcharge and they'll be ruined, possibly even dangerous, but even with NiCd or NiMH, too long a trickle can cook them so the goal would be to just put enough charge in to get your normal charger to work again. If they're Li-Ion, I'd err on the side of caution and charge them in/on a fireproof area, or better still, open the pack and check each cell voltage before proceeding. If any cell is below 2.4V, abort attempts to charge them. They are no longer safe. It would help to know the rate of the trickle charger and the voltage of the battery pack. If it's an 18V pack and only 12V trickle, depends on how the charger is designed, if it will float the voltage high enough to put enough charge into the pack to make the regular charger happy. Again it depends on the design and rate of the charger but using a 12V trickle charger for an 18V battery could take many hours to get much voltage increase - but don't assume, measure voltage instead because a modern design that's current regulated, could boost voltage enough and not even take an hour to get them high enough. I'd be monitoring the current and voltage and stop to see if it looks like you have a voltage consistent with all cells taking charge, or are suspiciously ramping towards a voltage that looks 1.2V too low (or multiples of 1.2V) like a cell is shorted. If it's a Li-Ion pack and it looks like 3.6V too low, abort further attempts until you take the pack apart to see what each cell voltage is. If a cell is shorted you may need to open the pack and zap those particular cells individually to burn through dendrites. This is only for NiCd or NiMH, never Li-Ion. Zap just means a fair amount of current, at least a few hundred mA but better a few amps, at a few volts (typically at least 6V or more works best). This is realized current not rated. In other words a humble 12V wall wart rated for 200mA, could possibly work because it (usually) has a capacitor after the transformer that provides enough instantaneous current. You only want to zap for a couple seconds, remove contact, then zap again until dendrites are burnt through, "if" you have any to burn as evidenced by a cell showing zero volts. Keep in mind that these are probably only temporary measures and the pack will have reduced capacity and be a problem in the future. If it's a nice drill and you have time to burn, you could rebuild the packs (if you have a decent soldering iron but technically you're supposed to use a spot welder too, to join the cells instead of soldering to their casings, although some cells are sold meant for battery pack building and have the nickel plated tabs already spot welded on and you just join those with a soldering iron), but otherwise new batteries or a new drill is the easier long term solution. There are good advantages to Li-Ion if they were NiCd or NiMH. Once you switch it is hard to look back.
 
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Messages
110
Location
KansasCity
If they are Lithium Ion batteries... trying to force a charge on them could end in disaster. They can explode and start a fire. If they are NiCad,IMHO it's not worth the effort to try and resurrect them. I've tried everything on NiCad (or NIMH) and have never had any success.
 
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9,796
Location
Jupiter, Florida
Originally Posted by JC1
I've got Dewalt 20v batteries that I've been using since 2011. Never an issue even if I leave them for months at a time.
I have the 12V and the 20V Dewalt lithium setups. So far, one of each type has "bricked", for no apparent reason. The 20V one was working fine one day and completely inop the next. The 12V one sat for a month and was bricked when I picked it up.
 
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Messages
1,627
Location
Cincinnati, USA
You can leave a Li-Ion battery sitting for months at a time but it must have enough charge in it that the self discharge doesn't put it under the minimum the protection board or charger will accept, and if you attempt to revive them, I wouldn't risk it if any cells are below 2.4V and even that is the lower range, better to consult the (individual cell, not tool brand) battery manufacturer datasheet to see what their minimum is. Then again, there's more than one fault a battery can have, extended runs heating up the protection board can cause damage over time too.
 
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Messages
9,986
Location
Waco, TX
In these situations, I cut an old battery pack apart, add wire and alligator/jumper clips, and turn them into "corded" DC drills that run off of a car/motorcycle battery (or two)
 

4WD

Messages
13,172
Location
Texas
I can see a 12v or 14v ... guess 18v is an ugly duckling for making "corded/battery" 🐥
 
Messages
1,206
Location
Lexington, NC
Originally Posted by Cujet
Originally Posted by JC1
I've got Dewalt 20v batteries that I've been using since 2011. Never an issue even if I leave them for months at a time.
I have the 12V and the 20V Dewalt lithium setups. So far, one of each type has "bricked", for no apparent reason. The 20V one was working fine one day and completely inop the next. The 12V one sat for a month and was bricked when I picked it up.
Same with my 12V Dewalt. It was lightly used but sat for some months then woldn't hold a charge. At that time they had a 2 year warranty; mine were a few months over that and Dewalt wouldn't even reply to my query about the warranty. Later ordered a cheap Chinese batt for the Dewalt drill and its worked fine for last couple years>
 
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820
Location
Upper midwest
Makita has a chip in it if you drain the battery past a point it kills the battery for good. Always put some kind of a charge back into a battery if you drain it. Don't drain it to nothing and leave it for a month or two or three. You may just run into the "disconnect".
 
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431
Location
Daytona Beach
I've fixed these before, by replacing individual "sub "C"" cells. I've tried all the internet tricks, like putting them in a freezer, all of it. Take my word for it, it's not worth it. I had a Craftsman 18V drill pack, actually 6 tools total, so I did buy new batteries for that. Cost about $79 for two NiCad's ! Also had a 20V L-Ion start to go weak on my Black & Decker hedge trimmer. I priced replacement batteries on the internet and found them for about $49.00 each. I figured that was way too much for a single battery. One day I was wandering around the tool isle in WalMart and found a Black & Decker drill kit that looked like the 20V batteries would work. I got 2 new batteries, a variable speed drill/driver with LED light, extra bits, a charger, and a carry bag for: You guessed it $49.00! And the batteries work perfectly in the hedge trimmer too!
 

JHZR2

Staff member
Messages
44,286
Location
New Jersey
Assuming the charger itself hasn't failed, and it's actively protecting, then replace the batteries. If you left them, they can self discharge below 2.0V on one cell. When that happens, the copper current collector starts to dissolve. If forced to charge again, those copper ions plate out. Get enough of them to plate, and a dendrite can form. Big enough dendrite and you'll pierce the polymer current collector. Then thermal runaway and major fire. Better safe than sorry.
 
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24,610
Location
Upstate NY
Thanks for the many answers,... Sounds like I should leave them alone and get a new drill....
Think beyond the drill. Buy into a battery system for cordless power tools and outdoor tools. I have Milwaukee M18 for almost everything except a Ryobi cordless 10" chainsaw. Milwaukee only makes a 16" and I wanted a 10" or 12".

DeWalt makes many quality tools as do others like Ryobi. Ryobi has a battery warranty if you register it.

I am just now trying some aftermarket battery packs as the OEM are high quality and high cost.
 
Messages
664
Location
South Carolina
Yeah I should just prob get a new one.... Debating if I REALLY need a drill or just a cordless screwdriver....
IMO everyone needs a cordless drill and 1/4" impact, so my vote is to look for a sale on the DeWalt, Makita, or Milwaukee 12V combo package at Home Depot or Lowes. The small impact wrench has become my go-to for virtually all jobs around the house as well as lighter stuff on cars.

As @Donald said, Ryobi is also solid but as far as I know they don't make 12V tools. The 18V are nice but the small size of 12V is preferred.
 
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