replacement batteries for cordless tools and other electronic battery packs

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I'd like to expand on an above thread about cordless tools. I think most of you will find this to be very useful information. When you have a cordless tool and the batteries die an early death, its not necessary to toss the cordless tool and go buy a new one, or to go shell out big bucks for a replacement battery pack. You may wish to go spend $$$ for all new equipment, or a lot of $$$ for a new replacement battery pack. Oftentimes the tool is like new, lots of life left in it, replacement battery pack non-existent or too highly priced, etc. Here's an alternative. Also, you can "soup-up" the battery pack with more power and energy.

This is also true for any rechargeable device, doesn't matter what it is. Cordless phones at home are a great example. You have a great cordless phone, you really like it, but the batteries are no good. Take it down to the battery store and slap in a new battery. Then you won't need to buy a new cordless phone, which would probably be made in China, and thats a whole-nother gripe I have! But thats another subject, Chinese made crap and human righs violations. But I digress, pardon me. For example, my 2 handheld ham radios were no longer holding a charge. Brand new replacement battery packs from the original manufacturer were obscenely priced. Since both radios were in mint condition and I didn't want to spend even more money replacing them, I decided to replace the batteries INSIDE the battery pack.

Since my old batteries were ni-cads, I didn't want to go back with ni-cads again. Ni-cads have charging and cycling problems, they will "short cycle" and in general they are not really desireable batteries to own. There is a new battery out called NICKEL-METAL-HYDRIDE ( NMH). These won't overcharge or short charge, and they can be partially charged with no ill effects, which is the bane of ni-cads. Also there are Lithium batteries nowadays too

Anyway, since I live in the OKC metro area, I was already familar with our 2 "battery stores". Now these guys don't sell car and tractor batteries and such, but anything smaller they will have or can get. Quite an inventory !!! Replacement batteries for hearing aids, cordless shavers, radios, anything unusual, etc etc yada yada yada, you name it, they got it. My point is, any medium to large sized city will have a store like this. Just get out the yellow pages and look, make a few phone calls.

Your battery pack can be re-opened and new batteries installed. Most you can do yourself, some might need a special soldering technique, and the store can do that for you if needed. Then close up the pack, charge it and go. One of my battery packs was easy to open, just carefully pried and worked the seam. The other one, i did not see a seam. The lady behind the counter took it, and in just a few minutes had it opened up using a little tool to cut it open.

Oh, I almost forgot. Here's the best part. You don't have to go back with Ni-cads and the existing voltage and milliamp rating. You can go back with a little more voltage. For example, instead of 7.2 volt, you can probably go up a little, say 9.6 or possibly 12 volt, without overwhelming the little motor. You DEFINITELY can go back with more milliamps. My old ham radio batteries were 600 milliamps. This allowed about a couple hour talk time. I went back with NMH 2,400 milliamp batteries. This gave me a 4-fold increase in useful time between charging. This one tidbit of information alone may make you decide to do your own battery replacement. You can decide just what you want your pack to do.

One can also look in a ham radio magazine, such as QST (go to barnes and noble, or borders, or better yet, get a ham radio license and join the hobby). Maha, Mr. Battery and others are manufacters and wholesalers. Both have 800 numbers and websites.

How did my little project go? I am so pleased. It would have cost probably $300+ to buy a new handheld dualband ham radio, and I would have had to learn how to use it, program it, etc. That would have been a real pain in the ol keester! A new OEM battery pack would have cost right at $100, and i would have been stuck with Ni-cads again. For about $30 I got NMH batteries and much longer talk time. The other battery pack cost a little more, as I paid them a few bucks for their labor to open and close the case. Absolutely still worth it.

Also, for example, lets say many folks that use tools a lot, say a carpenter, might have a really good cordless drill and several battery packs, using one while the other is charging. Double-whammy when time to replace batteries. Economies of scale, I am saying, lol. Reduce, Reuse, Recycle.

Have a good day and take care

Gene

-- gene ward (gward34847@aol.com), February 23, 2001

Answers

Good advice Gene. I have been doing this for several years and am very pleased with the initial performance increase. I have also found a few suppliers on the WEB (not here main line, but they do carry batteries relating to their product line).

I have also bought a few really good battery powered tools at yard sales that did not work. Generally cost a buck or two and with a new battery they are better than new.

-- Lynn Goltz (lynngoltz@aol.com), February 24, 2001.


Gene: Question: Is there any problem using a charger that says "use only for Nicad batteries?" Sounds great otherwise, if it works with the chargers intended for nicads. Jan

-- Jan in CO (Janice12@aol.com), February 24, 2001.

Yes Gene, can you give us any tips on charging the new, higher voltage, battery pack? Thanks.

-- john hill (john@cnd.co.nz), February 26, 2001.

The NMH batteries will charge up automatically just as the old ni- cads do. Not a problem. The only thing that can't be recharged is the old-fashioned batteries, by that i mean the regular batteries and the alkalines----the throwaways.

gene

-- gene ward (gward34847@aol.com), February 26, 2001.


Hi, Came across this 'thread' while doing some design work which need NMH or nicads. If I may add one thing. Your have to watch out for certain circuits that use smaller cells. The reason is that some designers don't use current limiting circuits. They use the smaller batteries to act as automatic current limiting. Robert

-- Robert (euclid@catskill.net), June 09, 2001.


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