Thread: Replacement power tool batteries.

nimh is vastly superior to nicad

Hi
I notice ebay is always selling dewalt batteries
might be worth a look and compare
www.ebay.com.au
cheers
Jedo

NiMH batteries should NOT be charged in a NiCD only charger.

There are many combination chargers around that will work with both; but check to make sure that it states that it can charge NiMH, otherwise you run the risk of the NiCD charger not detecting that the NiMH batteries are fully charged - whereon the charger will happily keep pouring energy in till the cells reach their burst point. Burst in this case meaning bits of hot metal flying around after a loud 'pop'. Not terribly exciting, but it can make a horrible mess on the kitchen bench.

If you decide to try it, monitor the battery temperature and stop if it gets over about 50 degrees.

Hi Dean,

I'm going through the same process except mine are 18v makita 2.6mh Nimh(4 in total). They were in constant rotation on the chargers. They have copped a flogging and after 3 years of constant use (renovating and building non stop) they have finally faded to where its a waste of time recharging. The makita charger will do both NiCad and Nimh. After talking to the guys at Battery world in brisbane I think I will going back to NiCads.

The reason being as I have finished Building and renovating and the tools only get ocasional use now, They reckon that the nicads would last longer then the nimh if i wasn't wasn't using them as much. Several people have told this from various places and forums.

If anyone can tell me and differnet, only to happy to listen.

Cheers

Michael.

Here's some of the replies I received on the other forum I posted this question on.

Originally Posted by another forum member

nimh has more charge capacity, but self discharges quickly. That's the pros and cons.
Nicad will keep its charge better when the tool is packed away, meaning you won't have to charge it every few days. But if you use the tools that much that the nicads go flat at the end of the day, well then you won't lose much going to nimh, and will get a larger capacity. So it all depends on usage.
My old makita nicad drill comes out about 4 times a week, so very little use, and I hardly ever have to charge it (only after extended use), when the battery in the drill is flat, I take the other one out of the case and put that in, and I get back to work.
On the other hand, another tool I have uses nimh, I have to charge it every three days, regardless of use. Eg, I have to charge it on sundays, otherwise it would be 1/2 flat just sitting in my van over the weekend.

Originally Posted by another forum member

My understanding (and it might be out of date) is that NiCds are better at high discharge loads than NiMH. So the 'best' cell type may depend heavily on how hard you use the tool.

I use a bucket load of NiMH AAs and while they were great when new, now they've got a year or more on them, their behaviour is as Pablo_H describes - excellent capacity the day they come out of the charger, but a few days later and you start to wonder if you really charged them.

And my reply that I wrote, including an answer to an email I sent to Akkupak

Originally Posted by Tas_Dean

Very interesting what you have said regarding NiMH not liking high current loads. The way I abuse my drill and cordless circular saw, I certainly give it hell with high current!

With that info I'm leaning towards spending a little more on the NiCd batteries from Akkupak. This is what they had to say when I asked about their aftermarket batteries and the genuine DeWalt batteries that they also sell. I made mention of my experience of DeWalt batteries being fairly poor quality, and that a search of the internet seems to relate the same.

Quote:
<table border="0" cellpadding="6" cellspacing="0" width="100%"> <tbody><tr> <td class="alt2" style="border: 1px inset ;"> Originally Posted by akkupak
I can understand your comments about the original batteries.
Yes the replacement packs do have Sanyo or Panasonic cells as well as the repacks we carry out.
The BCD-DW9095HC is a particular model that we have the factory prepare for us with Sanyo CP2400SCR cells inside. These are Japanese made high rate, fast charge cells that do have good performance in power tool batteries that have a high current demand. It is the same cell as we use in repacking and I am sure that you would find them to be reliable.
</td> </tr> </tbody></table>
Any more comments from anyone regarding NiMH? Information from Dewalt suggests that my charger is NiMH compatible.

Cheers, Dean

Can anyone confirm any of this info? I was lead to believe that NiMH was vastly superior to NiCad, but from the information I have seen it seems to be a case of horses for courses!

As I said in the post of my own that I have quoted, I'm leaning towards Akkupak as they use brand name cells designed for fast charging.
Does anyone know what cells the other places use?

Cheers, Dean

Hi Dean,

From my experience Nimh like to be used constantly. They charge quick, I have a car charger as well as a mains charger and they both work equally as well. They have a larger capacity then most NiCads. They dont like being left on a shelf and used occasionally. They will wear out a lot quicker if not used correctly.

I find the NiCad batteries i have for my 9.6v makita last a lot longer if left on the shelf. They only get occasional use and are always reasonably charged when i need to use them.

Like most people have sais in other posts. Horses for courses. If you are going to be using your tools everyday for a couple of hours a day. Then the Nimh are probably the way to go. Otherwise I would stick to the NiCad's. Thats what i'm about to do, replace the Nimh with Nicads. I knows it less amp hours but I wont be flogging them like they have been.

On the subject of cells in battery packs. You will find most brand name tools will use cheap to reasonable cells in their packs. This makes then more affordable to the public. When you get them repacked they will put either Panasonic, sanyo or maybe technica cells in them. They cost a lto more then the original cells but will last a lot longer. Thats the theory anyway.

It's a tough decision and it all comes down to your needs and use of the tools. From memory the NiCads are a bit cheaper then Nimh as well.

Cheers

Michael.

Just bought a replacement battery pack for my 14.4V Makita as the two NiCds no longer hold much charge and the reno is just starting in earnest. Paid extra for the NiMH battery since it had higher amp hour rating and my drill came with dual NiCd/NiMh charger......price difference between NiMH and NiCd was about $60 for the PowerCell brand battery.....so far it has be very good.

I have bought from electronic parts (a video camera battery)
I got the battery pretty quickly, and it seems to work well, although I dont use it all that much.

I ended up buying a 2000mAh Nicad from www.batterycharger.com.au. I'm pretty sure it's the same company as www.electronicparts.com.au (same checkout, product codes etc).

I ordered it last Wednesday afternoon, and it arrived early this Tuesday. So far I'm happy, it fits the tools well, the drill has got plenty of grunt again, and I haven't recharged it yet, but it hasn't really got much of a workout yet. I'll let you know in 12 months what I really think of it!

I contacted the three websites listed above, and apparently they all use panasonic cells in their batteries, so they should be good quality.

I chose NiCad over NiMH as I received conflicting information as to whether my charger was compatible or not, so I chose to stick to what was a safe bet!

Goodonya for reporting back

Be interested to hear the longer term opinion.


Cheers....................Sean

Scooter,

I have had personal experience with a company in Sydney called WES components. They sell replacement batteries for any and all drills (well almost all...) at prices that sometimes leave others blushing.

They can be reached in sydney on 02 9797 9866.

With my work we had this kick ass metabo drill ($600!!!) but every 2 years would eat the batteries...at $170 each genuine. The replacement NiMH from WES were $98 and they are still going strong.

I have no affiliation to WES other than a very satisfied customer - my work spends about $15-20K per year with them and they have a staggering range of electronics and assorted stuff:

http://www.wagner.net.au/catalogue/index.htm

For all on the forum - well worth a look - the catalogue is downloadable in chapters in PDF format.

Scott in Peakhurst.

Thanks Scott, will check out the link.

http://www.batterymaster.com.au/index.php

As Promised, a further update. My other dewalt battery has died altogether, so the replacement pack is the only one I have. Considering it has been getting hammered fairly hard, it seems to be holding up well!
Only problem I have now, is that the battery charger has died (unrelated to the battery - the builder who was borrowing my tools left the charger in the rain.

Anyone got a spare 18V dewalt battery charger laying around? After pricing a replacement, I'm willing to pay!