Rejuvenating NiCad batteries ?

Joined
14 Jan 2013
Messages
16
Reaction score
1
Location
Suffolk
Country
United Kingdom
I have 3 Makita 14v batteries for my drill/ screwdriver. They are about two and a half years old. Not heavily used, in fact laying in the garage for weeks at a time. Today they seem very poor, and although the charger says they are charged, they last only a few minutes. Is there anything I can do to revive them ?.

Suffolkman
 
Sponsored Links
Joined
1 Mar 2009
Messages
1,948
Reaction score
165
Location
Blackpool
Country
United Kingdom
The only way to do a proper rejuvenation is to cycle them a couple of times by a total discharge followed by a full charge. But from the sound of it they are boll*xed. I had to replace mine a couple of years ago and found them at a firm in scotland (OEM). can't find the ref at the moment.
 
Joined
14 Mar 2006
Messages
18,646
Reaction score
2,180
Location
Kent
Country
United Kingdom
Makita batteries are cack, have a brand new one which wont take a charge.The 'Site' batteries which fit are half the price and twice the quality.
 
Joined
14 Jan 2013
Messages
16
Reaction score
1
Location
Suffolk
Country
United Kingdom
Makita batteries are cack, have a brand new one which wont take a charge.The 'Site' batteries which fit are half the price and twice the quality.


Yes I have been discharging them with a car bulb, then recharging, dont know if it is working yet. Foxhole...what doo you mean by site batteries...have you got a link to some ?.
 
Joined
4 Jan 2013
Messages
1,728
Reaction score
233
Location
Angus
Country
United Kingdom
A couple charge discharge cycles should show if there's any benefit to be gained by rejuvenation, but I would reserve the light bulb discharge for later.
Start with a fully charged (according to your charger) battery and twist a bit of electrical wire rubber band, or anything that will keep the trigger engaged, put this on a surface in an other room (the constant noise can be annoying) close by where you can check the time it takes to stop turning the chuck, recharge the battery and repeat this process. Now check the time the second experiment takes to discharge the battery and write this time down, repeat and if there's any significant difference, your battery is good to go. Next step pop your battery in the freezer for 24 hrs, allow 24 hrs. to thaw and dry at room temp then recharge again and use in the drill, if there's no overall improvement then you might want to give up the ghost and bye a new one...pinenot :)
 
Sponsored Links
Joined
4 Jan 2013
Messages
1,728
Reaction score
233
Location
Angus
Country
United Kingdom
Never heard that one before ch :confused: But reducing crystal size is right on the button, If it does work putting a used battery pack on a vibration plate, Hmm...pinenot :)
 
Joined
22 Oct 2012
Messages
13
Reaction score
0
Country
United Kingdom
Thanks Pinenot, sounds like this is worth a try. I have been cycling them for a couple of days now. I notice that one retains it's voltage better than the other two.
 
Joined
28 Mar 2008
Messages
6,300
Reaction score
680
Location
Sussex
Country
United Kingdom
kept my old dewalt batteries going for about another year,by having 50 volts shot through them every now and then.
this blows off the crystals.
 
Joined
4 Jan 2013
Messages
1,728
Reaction score
233
Location
Angus
Country
United Kingdom
It's the combination of both the voltage and amperage that cause the effect, therefore 12V at a high amperage does the same i.e. car battery.
Crystals (for those who want to know) is a good word to describe it and when one of these crystals grows large enough to break through the folded carrier plate (inside one cell) that's when the battery is effectively dead.
Of course that's a simplistic description but does explain in elementary terms what happens. It's the quantity and quality of these crystals that determine the eventual output of any rechargeable battery, the more and finer formed crystals - the more available power both amperage wise and time wise. By altering the impute of electric charge (Zapping) the crystals formed can be different from the current status of charge given by most chargers. That's not to say all chargers are the same, smart chargers follow the above principals in so much as they vary the charging conditions according to the feedback they get from the battery placed on charge and by doing so vary the possible crystal size and configuration, this is also what battery conditioners do, it's almost like giving the battery an internal spring clean, so to speak...pinenot :)
 
Sponsored Links
Top