Difference Between Li-Ion and Nicad Chargers

Little Bill

Moderator
Staff member
Location
Tennessee NEC:2017
Occupation
Electrician
What exactly is the reason you can't charge Lith -ion batteries in a Nicad charger? I know you can't or are not supposed to, I just would like someone to explain what actually goes on as far as the differences in the chargers.

What I'm up against is I have 2 different Dewalt battery sizes. A 14.4V and 18V. Both of my 14.4V batteries have died, or at least won't hold a charge for more than a few minutes. I would like to change to Li-Ion batteries and get a charger that will do both types of batteries.
The batteries are so expensive that I hate to buy them because you can sometimes buy a new tool with 2 batteries and a charger for about the same as just the batteries. But I don't really need another tool either, hard choice.

Also, I like the feel of my 14.4V drill vs my 18V drill. Should I just try and find a deal on replacing just the 14.4V Nicad batteries with Nicad, or switch to the Li-Ion batteries?
Surely some of you have faced this. What are your thoughts on this?
 

Hv&Lv

Senior Member
Location
-
Occupation
Engineer/Technician
What exactly is the reason you can't charge Lith -ion batteries in a Nicad charger? I know you can't or are not supposed to, I just would like someone to explain what actually goes on as far as the differences in the chargers.

What I'm up against is I have 2 different Dewalt battery sizes. A 14.4V and 18V. Both of my 14.4V batteries have died, or at least won't hold a charge for more than a few minutes. I would like to change to Li-Ion batteries and get a charger that will do both types of batteries.
The batteries are so expensive that I hate to buy them because you can sometimes buy a new tool with 2 batteries and a charger for about the same as just the batteries. But I don't really need another tool either, hard choice.

Also, I like the feel of my 14.4V drill vs my 18V drill. Should I just try and find a deal on replacing just the 14.4V Nicad batteries with Nicad, or switch to the Li-Ion batteries?
Surely some of you have faced this. What are your thoughts on this?
One of the complaints I hear is that with the new batteries the drill won't stand up, or be as stable because the Li-ion batteries are too light. Of course, if you lay your drill down, that shouldn't be a problem.
Also the Li-ion batteries will give you full power until they are out. Unlike a Ni-cd, when a Li-ion goes out, it is done.
Check the dewalt site, there are one or two of their chargers that will work for both styles, and your 14.4 and your 18 V batteries, all in one. I think Lowes has one for about $80.
I think the charger difference has to do with the cell voltages of the different batteries.
 

Little Bill

Moderator
Staff member
Location
Tennessee NEC:2017
Occupation
Electrician
I had done a Google search but didn't get any answers other than to not do it.

I did find some info in the link posted.
However, I can't get my head around some of it such as, it says the NiCad batteries are charged with constant voltage and Li-Ion are charged with constant current. I don't under stand what is meant by that as there would be current involved with both types.:?
You won't have current without voltage!
 

Smart $

Esteemed Member
Location
Ohio
...
However, I can't get my head around some of it such as, it says the NiCad batteries are charged with constant voltage and Li-Ion are charged with constant current. I don't under stand what is meant by that as there would be current involved with both types.:?
You won't have current without voltage!
True... but the non-constant parameter varies.
 

__dan

Senior Member
There have been a ton of Li-ion battery fires, including fires in aircraft from laptops, PDA batteries. Those would be good devices used properly, so I'm assuming insurance would pay. There have been lots of expensive product recalls, Sony comes to mind, and heavy charges. There was a big liquidation of Bosch Li-ion cordless tools a few years ago and I bought a large amount. It was "fire sale" pricing. I suspected they were clearing out an older battery style.

Not sure, but as far as I know, Toyota still uses NiMH in the Prius. It would have to be an ongoing Li ion fire safety concern since the Li ion battery is much lighter.

It does not matter if it can be made to work or not. Can you imagine how liability would assign from a Li ion battery fire found in your nicad charger.

Amazon had this set for $149 delivered in January. Watch and wait for the liquidation sales.

http://www.amazon.com/Bosch-CLPK232-181-18-Volt-2-Tool-Combo/dp/B005GT0IXO/ref=sr_1_42
 
Last edited:

petersonra

Senior Member
Location
Northern illinois
Occupation
engineer
A fair number of these type of batteries are made up of a number of smaller batteries of standard sizes (AA, AAA, C, D).

In many cases you can repair the old battery by replacing the old nicad batteries with new ones, and not horribly expensively either. If your charger handles both NiCad and NiMH batteries, you can upgrade to NiMH in the process.

Want some cheap AA batteries? Open up what looks like a dry cell battery with the spring terminals on them. The battery companies no longer make these size batteries for the most part, but just package a bunch of AA cells inside that package.

Some 9 volt batteries are made up of a stack of button cells.
 
Last edited:

hurk27

Senior Member
All Dewalt chargers that do both have a yellow case, the black case chargers are for Ni-Cad only.

Some pointers in making your batteries have a long life:

The more you cycle the batteries the more it removes material from its plates, so running batteries till they are completely dead is not good for them, and this is a myth that was carried on from the original development of Ni-Cad batteries, NIMH or LI-Ion has never had this memory problem, and all newer Ni-Cads since the late 1980's have also not had this problem but myths carry on.

I still have 2 Ni-Cad 18 volt batteries from my original tool kit I purchased back in 1998 and they still hold a fairly good charge, I contribute this from reading up on batteries and how letting any chargeable battery lay around without a full charge on it will allow the electrolyte dissolve the plates in the battery, this goes for wet cells as well as dry cells, we all know that if you leave a dry cell lay around it will start leaking if it is not fully charged, this is because the case is one of the plates, of course over the years they have sealed the case in plastic so this doesn't happen but under the plastic the plate are still eaten away.

So in essences, using a full sine wave inverter on all my chargers in my van, I make sure every battery I have used goes back on charge even if I drill one hole with it or make one cut with my saw, all dewalt chargers are float type chargers and they will maintain a full charge without over charging.

This is also important for your car batteries, boat, and even generator systems, back a few years ago Generac use to install a trickle charger to maintain the battery in the generator, what the engineer didn't realize was maintenance type batteries were no longer readily available as maintenance free batteries flooded the market, these trickle charger do not shut off, and are always charging, this causes the battery to loose water and since you could not add water to these batteries would run dry, and in some cases would explode from hydrogen/oxygen build up, I wrote a e-main to one of their engineers who e-mailed me back and said he understood this problem and well we not have float chargers on Generac generators.

Most of my Dewalt batteries are Li-Ion now since they will fit older drills and newer ones, but I still have a few good Ni-Cad's and since the yellow Dewalt chargers charge both, I keep both on the truck, I have then mounted on the floor up front plugged into a strip that is plugged into a 400 watt full sine wave inverter (Dewalt chargers don't like modified sine wave) and if I leave the job site all the batteries are put back into each charger, and at a glance I know which has a full charge for the next job.
I have 4 dual chargers between my seats and all the dual chargers with the yellow tops charge both. these chargers can be found at Loews with one Ni-Cad battery for about $99.00 when they are on sale.
 
Last edited:

hurk27

Senior Member
Oh and I know that some manufactures will still say to run a battery down before charging, I showed this to a engineer who works for a very large battery company and he cracked up, and said guess they need to sell more batteries, because that is all it is doing, destroying the plates.
 

Little Bill

Moderator
Staff member
Location
Tennessee NEC:2017
Occupation
Electrician
All Dewalt chargers that do both have a yellow case, the black case chargers are for Ni-Cad only.

Some pointers in making your batteries have a long life:

The more you cycle the batteries the more it removes material from its plates, so running batteries till they are completely dead is not good for them, and this is a myth that was carried on from the original development of Ni-Cad batteries, NIMH or LI-Ion has never had this memory problem, and all newer Ni-Cads since the late 1980's have also not had this problem but myths carry on.

I still have 2 Ni-Cad 18 volt batteries from my original tool kit I purchased back in 1998 and they still hold a fairly good charge, I contribute this from reading up on batteries and how letting any chargeable battery lay around without a full charge on it will allow the electrolyte dissolve the plates in the battery, this goes for wet cells as well as dry cells, we all know that if you leave a dry cell lay around it will start leaking if it is not fully charged, this is because the case is one of the plates, of course over the years they have sealed the case in plastic so this doesn't happen but under the plastic the plate are still eaten away.

So in essences, using a full sine wave inverter on all my chargers in my van, I make sure every battery I have used goes back on charge even if I drill one hole with it or make one cut with my saw, all dewalt chargers are float type chargers and they will maintain a full charge without over charging.

This is also important for your car batteries, boat, and even generator systems, back a few years ago Generac use to install a trickle charger to maintain the battery in the generator, what the engineer didn't realize was maintenance free batteries were no longer readily available, these trickle charger do not shut off, and are always charging, this causes the battery to loose water and since you could not add water to these batteries would run dry, and in some cases would explode from hydrogen/oxygen build up, I wrote a e-main to one of their engineers who e-mailed me back and said he understood this problem and well we not have float chargers on Generac generators.

Most of my Dewalt batteries are Li-Ion now since they will fit older drills and newer ones, but I still have a few good Ni-Cad's and since the yellow Dewalt chargers charge both, I keep both on the truck, I have then mounted on the floor up front plugged into a strip that is plugged into a 400 watt full sine wave inverter (Dewalt chargers don't like modified sine wave) and if I leave the job site all the batteries are put back into each charger, and at a glance I know which has a full charge for the next job.
I have 4 dual chargers between my seats and all the dual chargers with the yellow tops charge both. these chargers can be found at Loews with one Ni-Cad battery for about $99.00 when they are on sale.
Please explain the part in red. Do you have a meter/charge indicator on the chargers?
 
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