Welcome to our site!

Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

  • Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

Cordless hand drill/driver

Status
Not open for further replies.
Hi all

As a self employed Joiner I have the annoying problem with the batteries of my cordless drill slowly dieing on me.This problem can take months of use to start happening but even after a full charge they don't last as long as they did when first purchased.

Now some of these drivers can be quite expensive so replacing batteries is something I can do without.

Is there anything I can do one to prevent them dieing on me and two to revive ones that have lost most of their power?

Why does this happen?

Cheers
 

crutschow

Well-Known Member
Most Helpful Member
Rechargeable batteries do have a limited life and eventually wear out by losing capacity. When that happens their's likely nothing you can do to recover that capacity.

When do you recharge the batteries? It may prolong their life if you recharge them before they are completely discharged. Completely discharging them can cause the cells with slightly lower capacity to become reversed charged as the other cells are still discharging, which can damage them. Recharging them before this happens is thus desirable.
 

BrownOut

Banned
Are they NiCad's or NiMH? All my old NiCads have perished. Newer NiMH work much better. Still, crutshow's advice might be helpful.
 

Ross Craney

New Member
Make sure you buy quality brands. I only use Bosch or Makita. While the "cheap" Chinese stuff isn't too bad for the price, it is ALWAYS the battery that lets it down. Check that the charger & battery has three terminals. The third is used for temperature sensing as the battery re charges & is a sure sign of a quality battery.
 

monkeybiter

Member
All my battery powered tools are NiCd which seem to me to be inherently unsuitable for the application. This could be because most of them are cheap brands or more likely it's a deliberate policy by manufacturers to maintain sales, because by the time you give up on a battery the chances are that model is no longer available for a replacement, so most people's only option is to buy new again [or buy two or more batteries in the first place].
 

BrownOut

Banned
by the time you give up on a battery the chances are that model is no longer available for a replacement [or buy two or more batteries in the first place].

That's what happened to all my old Nicad tools. I just went back to plug-ins.
 

Dean Huster

Well-Known Member
If you're serious about cordless tools, move over to Li-Ion batteries. I have a Hitachi drill/driver that I'm very satisfied with. No self-discharge, fast recharge, high torque. I use this thing professionally nearly every day in a home repair business, doing simple drilling, mixing paint, installing cement board, building decks. If I'm using it hard, the battery overheats before it discharges, so that can be a problem where having three or four instead of just two batteries would be nice.

Ryobi has a direct swap of their NiCd batteries to Li-Ion batteries -- same form factor for the battery stem. I just wish that Ryobi tools didn't suck to the nth degree. I own six Ryobi power tools and only one has yet to prematurely fail -- and that's probably because I've only used it twice.

Home Depot's Ridgid line has an interesting deal -- the products are warranted for life, free parts and labor to repair -- AND THAT INCLUDES BATTERIES ON CORDLESS TOOLS. I don't own any Ridgid power tools other than a shop vacuum (I like it) so can't tell you anything about reliability, etc. But that warranty is sure attractive and it'll probably be the next brand I try.

Dean
 

Vizier87

Active Member
I have something else to offer:
I also had a Starke cordless drill, and one day it died unjustifiably. I was already asking my dad to buy me another one, before I opened up the attachable battery pack, expecting a sludgy mess or something inside.
Guess what? There are 16 Ni-Mh batteries connected together inside and all perfect, except that the connectors are made of metal slivers which are rusty and some broke off entirely due to the rust.
So the rest is easy. Just solder copper wires on the battery terminals to replace the metal connectors, and, you know the drill. :D
Perhaps that's the case with yours. -shrugs-
 

bountyhunter

Well-Known Member
Hi all

As a self employed Joiner I have the annoying problem with the batteries of my cordless drill slowly dieing on me.This problem can take months of use to start happening but even after a full charge they don't last as long as they did when first purchased.

Now some of these drivers can be quite expensive so replacing batteries is something I can do without.

Is there anything I can do one to prevent them dieing on me and two to revive ones that have lost most of their power?

Why does this happen?

Cheers
One of the battery experts I knew a decade back said that cordless tools were the bucket that battery makers dumped all their rejects into. Not all are defective, but cordless tools suck up literally hundreds of millions of batteries and the makers have to sell them very cheap because of competition.

Added to that is the fact the batteries are being dicharged at high rates of current and they probably will have a cell or two flake out in six months.

Is there anything I can do one to prevent them dieing on me and two to revive ones that have lost most of their power?

Prevent from dying: charge slowly and don't overcharge severely.

Revive: no, there is no fix.
 
Last edited:

bountyhunter

Well-Known Member
Completely discharging them can cause the cells with slightly lower capacity to become reversed charged as the other cells are still discharging, which can damage them. Recharging them before this happens is thus desirable.
+1 The cell that "drops out" during discharge will reverse polarity in the string and the other cells will force current through it. It becomes a "load" for the other cells and they heat it up rapidly. That kills batteries faster than any other failure mode.
 
Last edited:
Status
Not open for further replies.

Latest threads

Top