what's up with nicad batteries?

[Anonymous]

We use a fair amount of batteries, mostly aa and aaa, to power various
gadgets. I would be willing to invest in nicad batteries if they really
worked, but the last time I did that about 5 years ago, they did not
hold a charge very well.

Have things improved any? Does the kind of charger you use make any
difference?

Any recommendations?

Thanks
..

 

[Eeyore]

We use a fair amount of batteries, mostly aa and aaa, to power various
gadgets. I would be willing to invest in nicad batteries if they really
worked, but the last time I did that about 5 years ago, they did not
hold a charge very well.

Have things improved any? Does the kind of charger you use make any
difference?

Any recommendations?

Nicads have been eclipsed by NiMH batteries.

Both have suffered from loss of charge issues but recent NiMH technology from
certain manufacturers has improved that. Sorry but I forget which brands
offhand.

Graham

 

[Eeyore]

They've been mostly replaced by Nimh batteries. Neither type were
designed to hold a charge for a long time while setting unused. They
are fine for things like cameras and other high demand devices, if you
know when you're going to use the device or you can leave the
batteries on charge until needed. For things that have a low power
drain over a long period of time, such as remote controls, rechargable
batteries aren't very useful.

For sure in the past, an alkaline battery would have been the best bet in such
situations.

There are a few manufacturers of improved NiMHs who are now selling them 'ready
charged' just like alkalines. Apparently they will hold at least 50% of their
charge for a year.

Graham

 

[Ecnerwal]

We use a fair amount of batteries, mostly aa and aaa, to power various
gadgets. ....
Any recommendations?

Use NiMh. But it matter both what you are using them for/in, what
charger you use, and how well you maintain things.

If you believe in memory effect, please go flush your brain until you
don't, or until you only believe that it applies to specific situations
run into on satellites with NiCd - and you're being told to get NiMh.

Running rechargables "totally flat" is bad, leaving them flat is worse
(if you must run them "out", then recharge immediately). Recharge early
and often is the current conventional wisdom.

If not using them for a month or more, recharge them every month, or
you'd have been better off with non-rechargeables.

Putting it in a long-term low-draw item like a clock - buy a
non-rechargeable.

Charger - I like a "smart" one - present version I have will charge 1-4
cells to 80% in 15 minutes - has temperature sensing, a fan, charges in
pulse mode, doesn't fry batteries that are left in it for days or weeks.
Could be a bit better in that it does not have a definitive indication
when it's done with the last of trickle charging, but it does what I
want one to do, having had poor experiences with trickle-charging
versions.

Sets. Mark batteries to maintain "sets" to fit your appliances, and
keep/use/charge each set together.

Shop carefully - you can easily pay 3-4X the price for exactly the same
thing by shopping carelessly, or you can be mislead by something
described as a "rapid" charger which defines "rapid" as "8 hours"
somewhere in the fine print. Look for larger packages of batteries,
which might be cheaper per battery - 20 packs, for instance.

Works for me. I've been feeding them to the heavy-draw AA stuff around
here and it's been working fine for several months - no way to tell how
it will be in the longer long term, but it's already cheaper than
disposables would have been (mostly because those cost so much).

 

[Daniel Who Wants to Know]

I primarily use Energizer, but have some Duracell AAA's as well. The
odd thing is that the D cells have 2500mah, just like the AA's. They are
no heavier, and have no more power...

That is because they are just the AAs in an adapter sleeve to make them fit
in the place of a D. They have them in a C size adapter also. When I first
saw these faux C and D size rechargeables at wal-mart I wanted to slap
sombody. You can buy the sleeves here
http://www.greenbatteries.com/battery-adapter.html (it is the first link I
clicked on from a google search)

 

[Arnold Walker]

That is because they are just the AAs in an adapter sleeve to make them
fit in the place of a D. They have them in a C size adapter also. When I
first saw these faux C and D size rechargeables at wal-mart I wanted to
slap sombody. You can buy the sleeves here
http://www.greenbatteries.com/battery-adapter.html (it is the first link I
clicked on from a google search)

Used to have them at Walmart ,but they vanished about 5 years ago.

 

[Arnold Walker]

Use NiMh. But it matter both what you are using them for/in, what
charger you use, and how well you maintain things.

If you believe in memory effect, please go flush your brain until you
don't, or until you only believe that it applies to specific situations
run into on satellites with NiCd - and you're being told to get NiMh.

Running rechargables "totally flat" is bad, leaving them flat is worse
(if you must run them "out", then recharge immediately). Recharge early
and often is the current conventional wisdom.

If not using them for a month or more, recharge them every month, or
you'd have been better off with non-rechargeables.

Putting it in a long-term low-draw item like a clock - buy a
non-rechargeable.

Charger - I like a "smart" one - present version I have will charge 1-4
cells to 80% in 15 minutes - has temperature sensing, a fan, charges in
pulse mode, doesn't fry batteries that are left in it for days or weeks.
Could be a bit better in that it does not have a definitive indication
when it's done with the last of trickle charging, but it does what I
want one to do, having had poor experiences with trickle-charging
versions.

Sets. Mark batteries to maintain "sets" to fit your appliances, and
keep/use/charge each set together.

Shop carefully - you can easily pay 3-4X the price for exactly the same
thing by shopping carelessly, or you can be mislead by something
described as a "rapid" charger which defines "rapid" as "8 hours"
somewhere in the fine print. Look for larger packages of batteries,
which might be cheaper per battery - 20 packs, for instance.

Works for me. I've been feeding them to the heavy-draw AA stuff around
here and it's been working fine for several months - no way to tell how
it will be in the longer long term, but it's already cheaper than
disposables would have been (mostly because those cost so much).

Been there done that for about 10 ten now.....on flashlights it don't harm
to get
led's if you using it a lot.On night deliveries led's and rechargeable
batteries last as many
as the old flashlights and non-rechargable did in days roughly.You have
throw that rechargable
out after 100th charge though I had some that last out to 200 charges.A lot
of what used was
RayoVac rechargable.

 

[[email protected]]

Nicads have been eclipsed by NiMH batteries.

Are Li -ions even better than NiMH tho?

 

[Eeyore]

Are Li -ions even better than NiMH tho?

Define 'better'. What criteria are important to you ?

Graham

 

[[email protected]]

Define 'better'. What criteria are important to you ?

Graham

Light weight and longer life, more torque maybe?

Something you could use to build say a deck outside
with...driving self tapping screws and such.

I know that nicad wont be a good bet.... but unsure of
NiMH or Li-ion units

 

[Eeyore]

Light weight and longer life, more torque maybe?

You mean current delivery I suspect.

Something you could use to build say a deck outside
with...driving self tapping screws and such.

I know that nicad wont be a good bet.... but unsure of
NiMH or Li-ion units

I'd suggest you start here. Both have characteristics that may be more or less
suitable than each other depending on the actual application.

Note that NiMH battteries have a significant self-discharge rate that renders
them unsuitable in applications that require a long 'standby' time. A couple of
manufacturers have improved this recently with new NiMH chemistry but it's still
a problem with most NiMHs.

http://en.wikipedia.org/wiki/Lithium_ion_battery
http://en.wikipedia.org/wiki/Nickel_metal_hydride_battery

Graham

 

[Bob Adkins]

That said, the Milwaukee and DeWalt Li battery tools kick ass. The Milwaukee is 28
volts with about twice the ah capacity and yet about 2/3s the weight. Both use newly
developed (but different) chemistries that deliver quite high currents.

If Li batteries are so great, why do hybrid cars use NiCd's in their
packs? Maybe because the Li cells are subject to catch fire?

I'm much more familiar with the Milwaukee because I have a friend who is an official
service center for Milwaukee and he shoots me all the V28 batteries that they
warrantee. Invariably one bad cell and the rest are fine. Amazing battery
management system inside the pack. Each cell is charged-managed individually.

If I didn't already have a rather full set of DeWalt tools I'd be right on top of the
V28 Milwaukee line.

Anyone tried the Ryobi tools? They have a "1 battery fits all" scheme.

I'm fed up with battery powered tools. There should be standards so
that all 12v, 14v, 18v, 19v, etc. fit all power tools of the same
voltage rating. If your drill breaks, you may have to throw away 2 or
3 good battery packs. If your batteries die, you may have to throw
away a perfectly good drill or saw because you can't find economical
battery packs . Phooey on that. Also phooey on $85 battery packs. You
can buy a decent drill with 2 batteries and a charger for $40.
-

Bob

 

[Eeyore]

If Li batteries are so great, why do hybrid cars use NiCd's in their
packs?

Which cars use Nicads ?

Graham

 

[[email protected]]

I'd hate to think how many deck screws my 10 year old 18 volt DeWalt cordless drill

has driven. NiCADs and not NiMH. NiCADS still rule for power density. That is, the
ability to deliver high current (and thus power) from a small package. The energy
density trails behind NiMH and Li but that's usually not an issue with a portable
tool.

Maybe I should stick with NiCad after all then? What
you think?

 

[[email protected]]

Anyone tried the Ryobi tools? They have a "1 battery fits all" scheme.

Was wondering abt that brand/model as well.

 

[Arnold Walker]

If Li batteries are so great, why do hybrid cars use NiCd's in their
packs? Maybe because the Li cells are subject to catch fire?


Anyone tried the Ryobi tools? They have a "1 battery fits all" scheme.

I'm fed up with battery powered tools. There should be standards so
that all 12v, 14v, 18v, 19v, etc. fit all power tools of the same
voltage rating. If your drill breaks, you may have to throw away 2 or
3 good battery packs. If your batteries die, you may have to throw
away a perfectly good drill or saw because you can't find economical
battery packs . Phooey on that. Also phooey on $85 battery packs. You
can buy a decent drill with 2 batteries and a charger for $40.
-

Bob

Part of the reason many carpenters use those big bucks to buy a compact
generator or powersupply...some like Milwaukee,DeWalt,etc. have a radine
generator fits all tools, not sorting thru a hundred pound stack of old
batteries and chargers to find your ??? tool battery or charger.Same story
on the temporary utility pole.....
when it finally comes.
Others gang battery the worktruck with an invertor and crank the truck every
so often to charge the battery or run that heavy load from a masson saw or
aircompressor.Diesel trucks (small diesel tractors are even better) do that
fairly well.In recent years even seen some looking at gasifing the wood
scraps at the job site .......to save on dumping fees and power the tools at
the same time.
And 110 ac tools will walk on battery tools with much more power to do the
job. And never running out of power
like batteries....well as long as you can keep it plugged into the ac outlet
and generator running,at least.
I need to take that back, a few cut the cord to a saw they were
using.....maybe need to add watch the cord,too.

 

[Arnold Walker]

Which cars use Nicads ?

Graham

Maybe the same reason as
Bell,Aerospatiale/Eurocopter,Sikorsky,Westland,Agusta,and Hughes use them
since the 50's and 60's.New design in and of itself ...is not good
enorgh,since Ellison at the turn of the century invented nickol-iron (the
first akaline,I think) batteries to improve his electric car range in the
early 1900's.The Ford model T won out over the Ellison electric car in the
end.

 

[[email protected]]

Part of the reason many carpenters use those big bucks to buy a compact

generator or powersupply...some like Milwaukee,DeWalt,etc. have a radine
generator fits all tools, not sorting thru a hundred pound stack of old
batteries and chargers to find your ??? tool battery or charger.Same story
on the temporary utility pole.....

You make a VERY compelling reason NOT to buy/use batter
based tools

You have me "rethinking" my idea abt doing so. Thanks

 

[Daniel Who Wants to Know]

If Li batteries are so great, why do hybrid cars use NiCd's in their
packs? Maybe because the Li cells are subject to catch fire?


Anyone tried the Ryobi tools? They have a "1 battery fits all" scheme.

I'm fed up with battery powered tools. There should be standards so
that all 12v, 14v, 18v, 19v, etc. fit all power tools of the same
voltage rating. If your drill breaks, you may have to throw away 2 or
3 good battery packs. If your batteries die, you may have to throw
away a perfectly good drill or saw because you can't find economical
battery packs . Phooey on that. Also phooey on $85 battery packs. You
can buy a decent drill with 2 batteries and a charger for $40.
-

Bob

Hybrids use NiMh not NiCd