cordless tool battery help

May 11, 2013, 09:30:36 AM

My batteries arent holding a charge very long when working with them. Is there a way to regeuvenate them or something I can do?

14.4 volt and 18 volt.

cordless tool battery help

Reply #1 – May 11, 2013, 10:13:04 AM

I send mine here - http://www.springgrovebattery.com/
It's about half the price of new and always hold up well. Maybe some place more local to you is offering the same services.

cordless tool battery help

Reply #2 – May 11, 2013, 10:13:27 AM

My local Interstate Batteries distributor will replace the batteries in your battery housings. It's much less than buying new ones.

cordless tool battery help

Reply #3 – May 11, 2013, 11:42:45 AM

what type of cells are these batteries you have?

cordless tool battery help

Reply #4 – May 11, 2013, 11:58:17 AM

in many cases, simply re-introducing your battery to a different potential will cure any memory it may have.

while i type this i am staring at my universal laptop power supply,
it says 80W, 19vdc output,, thats about 4.2A,, made by Kensington that i got from the local box store.
your 18v charger may have a much lower amperage ouput in order to achieve a "trickle" charge.
The problem with battery chargers of chordless tools is that only the very expensive ones have a list option feature to Equalize.
The laptop power supply i have would be ideal to put on your 12v battery for about 30seconds or so,, maybe a couple minutes then i would discharge that battery completely with a small light bulb.

this laptop charger may not be ideal for your 18v battery, it depends on the amperage output on your 18v charger.
If your 18v charger puts out low wattage / amps then yes., if it puts out like 20vdc with no load and its rated in amps like 2 or 3 ect then perhaps you gotta find a charger that has a little more kick to it. you would be surprised what treasures you find by checking out your various power supplies lying around.

size matters,,,, btw,, its likely you could easily find a charger lying around that is small in size , says its a 24vdc output but it has only 200ma rating,, it would be pointless to use that charger on your 18v batt because it would never get close to performing the function of an "equalize" charge.

your oem charger may have something similar on your 18v charger.

your 18v battery charger spec probably puts out well above that if its working properly.
usually they output of your chargers are a higher voltage output of lets just say about 10% more so that when you attach a dead battery, the load drops the voltage level to approx 18v.

If you have another thing around the house that puts out 18V with a different amperage/wattage spec, introduce the 18v battery to that charger for a little bit and observe / feel it for the first few seconds or even the first couple minutes. if all seems to be ok with the battery itself, i would even go as far as to let it charge for about 10min or more, this depends on the DC power supply amperage you are using.
depending on the battery you have, it may have a low voltage cut off circuit which is preventing you from discharging completely,, ive seen this in a Makita drill once with a built in light and such,, it has intelegent battteries...... bad idea imho... and i know batteries.

let it set for about 5min or what ever you decide then take it of this different charger and put a 194 , 1156 , test light or some sort of small bulb on the battery and let it sit for 24hrs to discharge.

place it back on your OEM charger and it should be back in the game for a few more jobs.

there are several levels of battery "states" such as
low voltage shut down
High Voltage shut down
Float voltage ~ ususally the exact name plate voltage + a half a volt or so
Boost or Equalize charge ~ ususally exceeds the recommended recharge voltage but is something done to batteries (in the battery industry at large) to help "equalize" the cells. (this is what i am attempting to get you to do). your battery has many many 2v cells that add up in series/parallel to give you the potential and the stored current.
Trickle charge

cordless tool battery help

Reply #5 – May 11, 2013, 12:52:49 PM

Quote from: jcassity;414908

what type of cells are these batteries you have?

Just normal ni-cad, I "assume".

Thanks for the nice write up, I appreciate it.

cordless tool battery help

Reply #6 – May 11, 2013, 01:08:54 PM

Ni-cads will tolerate the above situation i described.

not to carry on too much on the topic but when dealing wtih laptop batteries doing this,

simply introduce the laptop to a different power supply ***with the battery*** installed on the laptop.

stay within the battery voltage specs and just use a different power supply and those little adaptors they give you in a bag.

there is a vast amount of white papers on this topic on the net with respect to laptop batteries that have a chip in them that prevent recharge after "X" amount of deep discharges.

the only way around it for normal folk is to buy another battery.

cordless tool battery help

Reply #7 – May 11, 2013, 07:32:20 PM

upgrade to li-ion or li-fe cells.

you'll have twice the power and charge.