Step 3: Cordless drills/power tools

Sometimes you can select a power tool with a specific battery type. A good example is cordless power tools. Drills can be bought using NiCd, NiMH or Li-Ion batteries.

Recommended by toolmonger.com and myself:

Buy Li-Ion tools if you can afford it, otherwise buy NiCd. NiCds are supposed to have higher capacity for heavy duty power tools than NiMHs.


I actually own one of each, both made by Makita. The Li-Ion is nice because I can leave it for a long time and it still retains its charge. The NiCd will lose it charge in a few days and have to be recharged.

 The manual for my Makita Li-Ion drill says:

Charge the battery before completely discharged.

Change the battery when the drill starts to slow down.

Never charge a fully charged battery. Overcharging.

Let a hot battery cool to room temperature before cooling.


My recommendations Li-Ion power tools:

Do not discharge all the way.

Do not run in hot environment (if possible).

Charge often.


My NiCd drill and batteries are probably 8 or so years old so the batteries don’t last very long. I don't use it very often so I had to recharge a battery before I could use it.

I ran both batteries down a couple of times (see picture) by wrapping some house wiring around the switch and letting it discharge. After the batteries cooled off, I recharged them. They seem to run a little better and don't self discharge as much.

I also tried discharging my cousins Skil drill (see picture) a couple of times and saw a big improvement in run time.

I also stuck one of my NiCds in the freezer. Freezing NiCds is controversial. Several sites, including some manufacturers say you shouldn't do this. Some websites suggest doing this to get rid of memory problems. I tried this but saw no improvements.
Now most websites that do recommend freezing say you should put them in a plastic bag so that they won't absorb moisture. I agree.
Now many websites say freezing will greatly reduce the self discharge problem. This is the main reason I tried this.
PROBLEM: Most websites recommend that you take the battery out of the freezer and let it come back to room temperature. Now, for me this defeats the purpose as I just want to use my drill immediately. If I still have to wait a couple of hours, I might as well just put in on the charger instead of freezing it.
SOLUTION: Well, I decided to try it right out of the freezer. It seemed to work fine. Now I haven't experimented much with this and cannot recommend it.  But, at your own risk, you might try freezing your battery for immediate use. Make sure the battery is dry.

Power tool battery replacements:

Lots of stores and websites sell replacement batteries for power tools. Some places like Batteries Plus will actually replace the batteries in a power tool battery pack.  Most of these battery packs have multiple cells in them. Remember the standard NiCd battery is 1.2V so to get a 12 volt battery pack, there will probably be 10 cells in it.
Now I had a Hitachi cordless drill with two battery packs. They wouldn't hold a charge so I opened them up (see picture). Some of the cells appeared to be dead. I decided to take some battery cells from one pack and put them in the other one to try to make one good battery pack.
Failed: The first problem is that the cells are connected with those metal strips that are mechanically attached to the cell. Well, I was able to solder to them. But the biggest problem is that replacing a couple of  'bad' cells, just caused some others to fail.  After doing some research on battery packs, this is understandable.
Recommendation: If you want to replace cells in a battery pack, replace all of them with new ones with the same capacity and close to the original battery capacity. You might think higher capacity battery cells would last longer but it depends on if the battery charger can fully charge them.

Please recycle all old batteries. My local Home Depot, Ace hardware and Batteries Plus will recycle batteries.


My recommendations NiCd power tools:

Once every month or so, discharge all the way and recharge.

Do not leave on charger once it's charged.

Remove from tool if not being used for a while (Don’t know if this really helps and I don’t do this).

Now if you don't use your power tool that often, you will probably have to recharge it before use.

You might try the freeze method; see caveats above or just stick them in a bag and put them in your refrigerator.

<p>I was check out this website before buying ebook step by step battery reconditioning - http://bestbatteryrepair.blogspot.com. now I know how to repair battery, reconditioning old batteries is a great way to help the environment. Most people will throw out old batteries not knowing they can be restored to their original glory? Batteries are not cheap! Before throwing out any battery you should test them to see if they can be restored. restored to their original glory? Batteries are not cheap! Before throwing out any battery you should test them to see if they can be restored.</p>
<p>I went briefly through the article, there and found many wrong information:</p><p>&quot;NiCD - Once every month or so, discharge all the way and recharge.&quot;</p><p>yes, but do not make a deep dischagarde. once the tool getts sluggish, go and recharge. DO NOT turn it on and off repetably to discharge even more!</p><p>&quot;Li-Ion Leave the battery or device on the charger even after it&rsquo;s fully charged.&quot;</p><p>Why the hell would you want to do that? Li-Ion should strictly not be charged over 4,2V, that is why your charger stops charging at that voltage. If it would not, the battery will catch fire or explode!&uml; Depending on your charger, charger will be turning on and off to keep battery at 4,2V. This is also what happened in old poorley designed laptop battery - and as we all know destroyed te battery over time. So, NO, do not keep your Li-ION (or li-poly) connected to your charger for longer periods of time (etc. more than a day).</p><p>&quot;NiCds are supposed to have higher capacity for heavy duty power tools than NiMHs&quot;</p><p>WTF? NiCd are having LESS capacity than NiMHs, and they are more sensitivy to the memory effect than NiMh. Why are they still used? Because they can handle far greater currents than NiMh.</p>
I have a canon camera battery which seems to have developed a memory! It'll charge for 5 minutes but will only last about the same amount of time! <br>Question is how does one remove the 'memory' from batteries to allow them to take a full charge again?! <br>
Do you know what type of battery it is? Does it look like several cells in a pack. <br>If it's a memory issue, then it's probably NiMh or NiCd. For memory problems, I had the best luck in fully discharging the battery then recharging several times. Unfortunately, with a camera, it probably won't allow you to discharge very fully. What I would suggest is discharging it with a heavy resistor or maybe some LEDs. No guarantees. <br> <br>If it's several cells in a pack, then probably one of the cells is depleted. In my experience, there's probably not much you can do about that. <br> <br>LOG
It's an Li-Ion battery! a sealed unit for a canon camera ( BP-511 battery number)
The latest theory is that li-ion batteries do have memory issues. I found a website discussing problems with the BP-511. <br>http://photography-on-the.net/forum/showthread.php?t=1108699 <br> <br>I would suggest you try the last entry: <br>&quot;To correct the situation I would turn the camera on, set the screen to be constantly on and then allow things to totally discharge. I would have to do this 2 or 3 times and then the battery would be good for several hundred exposures (as intended).&quot; <br>Doing this should drain the battery slowly but more thoroughly than taking pictures especially using the flash. <br> <br>Hope this helps. <br> <br>LOG <br>
You should not mix different types of batteries. Nimh, nicad, alkaline. If your device uses 2 batteries, try to keep them together till death. Otherwise a new and old will not last as long, They will balance and will not last as long. Doodado
Rechargable engizier
I used to put my plain alkaline batteries in the freezer for a few hours take them out and use them again. It works for low power devices like for a Walkman. <br> <br>The trick is you don't just place them inside your freezer there is a way of doing it.
I am impressed I tried the method of freezing NiCd batteries. And it worked like a charm.
Oops I meant to freeze and then give it a good whack.
I'm glad it worked for you. I figure once they stop working, it's worth a shot trying different methods since they useless otherwise.<br><br>LOG
I had good luck with the battery packs for my drill but not much luck with AAA NiMh batteries.<br><br>LOG
Now I don't have to buy new drill batteries
Hay guys .. Do you know how to make a inverter dc to ac?????????????
DC to AC is pretty hard to do. One of the easiest ways is to buy a power inverter. But they only converter 12Vdc to 120VAC.<br><br>Here is a circuit to build a converter:<br>http://www.eleccircuit.com/dc-to-ac-inverter-by-ic-555-and-tip41-tip42/<br><br>I suspect it's not very efficient however.<br><br>LOG
Hey I have the same tooth brush.
WOW! <br><br>It seems all around you is rechargeable. Are you rechargeable, too? ;)<br><br>A bit: when you say &quot;...This is rather messy as (I believe) this is an acid.&quot;, that is not an acid, is an alkali. But it is so corrosive (or perhaps more) than an acid of the most common. <br><br>Great Instructable!
Some days I wish I were rechargeable.<br><br>You are right about it being alkali. I should have guessed when they're called alkaline batteries.<br><br>Thanks,<br><br>LOG

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