Need help again..Dewalt battery query

ali · Post by **ali** » Tue Nov 04, 2008 11:03 am

Dewalt Nail Gun with 3 x 2.4Ah XRP batteries.......

OR

with 2 x 2.6Ah Ni-MH Batteries.

Very similar price, around a tenner extra for the 3 battery version.

Bloke on phone (for 1st option above) tells me the 2.6's will eventually not hold a charge as well...and that there's really only a difference of around 50 nails worth of usage extra in them, compared to the 2.4's.

However that seems to go against another site which says 'complete with 2.6Ah NiMH batteries which have no memory effect therefore can be "topped" up or charged at any time without affecting battery life.'

Help please?

carhartt kid · Post by **carhartt kid** » Tue Nov 04, 2008 12:15 pm

Buy a paslode!!!

big-all · Post by **big-all** » Tue Nov 04, 2008 1:03 pm

you cant short charge nicad batteries as it knackers them by reducing the charge they can maintain

where as nmhi can be charged at any time

after several weeks off no use your nicads will run down maybe 80% which can be a pain because you are likly to run out off power before the first battery you put on charge is ready

where as with nmh you can charge one the night before and the second one whilst you have breakfast and hey if it hasnt finnished charging before you need to go out to the job no probs just finnish charging when you get there

Hoovie · Post by **Hoovie** » Tue Nov 04, 2008 2:37 pm

Like he says, basically.

The "Memory" effect referred to is that over time, depending on how the batteries are used and charged, they 'forget' how much charge they think they can hold, and how much charge means empty.
So when a battery reaches 75% full, it MAY think it is fully charged and won't take any more charge, so instead of getting 2 Hours of life, you only get 1.5 Hrs.

you can avoid this effect on Ni-Cad batteries by using the battery until it is totally dead (rather then just gone too slow for the tool) and then charging it until fully charged each time, so it goes through the full 100% full - 0% full - 100% cycle every time

It is possible to reverse this effect to a fair degree by re-conditioning the battery by following this process repeatedly, but a better idea IS to get Hi-MH or even Li-On if possible as the best (but most expensive) option.

ali · Post by **ali** » Tue Nov 04, 2008 3:02 pm

Thanks.

I know I'm very probably being thick here.......but are you all talking about the same thing?

Big-all.....nicad, nmhi

Hoovie....Hi-MH

Are the nicad the first 2.4 ones????? Or are they both nicad but different 'strengths' (female technical term there

)

Are the nmhi/Hi-MH/Ni-MH in all your posts, all the same things or different?

If they are all the same, judging by Hoovie's post, I'd be better with the kit with the 2 x 2.6's? Or have I got that wrong?

Sorry, mental block today.

Hoovie · Post by **Hoovie** » Tue Nov 04, 2008 3:21 pm

ali wrote: Thanks.

I know I'm very probably being thick here.......but are you all talking about the same thing?

Big-all.....nicad, nmhi

Hoovie....Hi-MH

Are the nicad the first 2.4 ones????? Or are they both nicad but different 'strengths' (female technical term there )

Are the nmhi/Hi-MH/Ni-MH in all your posts, all the same things or different?

Ni-MH is the correct name and stands for "Nickel-Metal Hydride" - the others (inc mine) are typos.
Ni-Cad is "Nickel-Cadmium".
Ni-Cad is an old rechargable battery technology.

ali wrote: If they are all the same, judging by Hoovie's post, I'd be better with the kit with the 2 x 2.6's? Or have I got that wrong?

Sorry, mental block today.

Ni-MH is a much superior option then Ni-Cads (Nickel-Cadmium) and if the XRP is a Ni-Cad battery, then the 2.6 Ni-MH set will be a better buy (assuming it is not way more money!)

the 3rd battery type I mentioned is appearing in power tools are Li-on (Lithium-Ion), also referred to as just Lithium (unless the two are subtle variations of the same thing?)
These are the new kids on the block, and provide features such as much greater power for the same battery physical size and a more rapid recharging.
The Li-on battery is also the ONLY way to effectively eliminate the Memory Effect - both Ni-Cad and NI-MH suffer from the memory effect, but Ni-MH is less pronounced.
Li-on are intelligent batteries that do not suffer from this generally BUT very often, they can only be charged a number of times before they will refuse to charge again (talking in the many hundreds here though)

ali · Post by **ali** » Tue Nov 04, 2008 3:30 pm

Thanks Hoovie.

Got it now.

Btw, I haven't seen the gun offered with a lithium option but I'll just double check that first before ordering.

Hoovie · Post by **Hoovie** » Tue Nov 04, 2008 3:42 pm

This question sparked my interest and I just did a bit of browsing and found this site .... battery university.

Turns out the Ni-Cad battery is not only old, but Queen Victoria was still on the throne when it was invented

Some interesting stuff on that site

OK........ "Hello. My Name is Hoovie and I am a Geek"

ali · Post by **ali** » Tue Nov 04, 2008 4:11 pm

Lol.

Will go look though......

big-all · Post by **big-all** » Tue Nov 04, 2008 5:01 pm

theres me thinking nimh didnt have a memory effect

also i alway say on nicads to never flatten beyond 95% to avoid the slim chance that a flat cell can reverse polarity

incidently i have had 2 batteries that have a cell that reversed [i assume !!!] a certain point on the battery got very hot shortly after charging starts followed by a loud pop as the battery goes taking the charger with it!!!

fin · Post by **fin** » Tue Nov 04, 2008 6:32 pm

i had a dewalt cordless with the xrp type batterys. there ni-mh only the really old ones are ni-cd and i mean really old like elu batterys

ive now got a dewalt cordless with the 2.0amp ni-mh batterys there fine.

the old cordless i had with the 2.4amp ni-mh batterys one of them went pop as i think i discharged it to much and was using a hole cutter at the time.

darrenba · Post by **darrenba** » Tue Nov 04, 2008 7:35 pm

You might find that the 2.4Ah nailer is the old model (DC618KA), according to the spec it came with Ni-Cd 2.4Ah.

http://www.amazon.co.uk/Dewalt-Dc618Ka- ... B0009VX31S

The new model DC618KB comes with the 2 x 2.6Ah NI-MH batteries.

http://www.dewalt.co.uk/powertools/prod ... o/DC618KB/

darrenba · Post by **darrenba** » Tue Nov 04, 2008 7:39 pm

You can also tell which model of dewalt battery you get from the colour of the battery.

Ni-Cd ones are all black

Ni-Mh ones are black & yellow

ali · Post by **ali** » Tue Nov 04, 2008 8:35 pm

Thanks Darren. I was wondering what the difference between the KA version and the KB version was.

darrenba · Post by **darrenba** » Tue Nov 04, 2008 8:47 pm

I bought the KB a few months ago and it's been excellent. I've not yet needed to use the 2nd battery.