Battery Charging?

[Harry Spillett]

I recently got a new, larger RX battery for my Raptor. I wanted a heavier
one to add some nose weight as well as add electrical capacity. I ended up
with a 2500mAh pack which fulfilled all the requirements.

However it wasn't until the other day when I was cleaning the heli that I
actually noticed what was written on one of the cells, they are 2500mAh
alright but they are NiMh and not NiCd. have been using the standard Futaba
charger for the initial charge and two additional charges, will I be
damaging the cells or will this charger be acceptable too?

Harry

[Peter Christy]

Harry Spillett wrote:

> I recently got a new, larger RX battery for my Raptor. I wanted a heavier
> one to add some nose weight as well as add electrical capacity. I ended up
> with a 2500mAh pack which fulfilled all the requirements.
>
> However it wasn't until the other day when I was cleaning the heli that I
> actually noticed what was written on one of the cells, they are 2500mAh
> alright but they are NiMh and not NiCd. have been using the standard Futaba
> charger for the initial charge and two additional charges, will I be
> damaging the cells or will this charger be acceptable too?
>
> Harry

A NiCad trickle charger will charge NiMH cells without problems, though due to
the larger capacity, you will have to leave them on longer to get a full
charge. If its a 100mA charger (typical) it will take 25 hours to charge a
2500mAH pack from flat........!

--
Pete
christy@NOattglobalSPAM.net
(make the obvious amendments to reply!)

[Harry Spillett]

Thanks Pete,

I asked around for the sums a little while ago and soon realised that this
pack would need a lot longer to charge than the original!!

I am glad to hear that the charger is OK for both types of cell

Harry

Peter Christy <christy@NOattglobalSPAM.net> wrote in message
news:jCUob.462$382.316@newsfep4-winn.server.ntli.net...
> Harry Spillett wrote:
>
> > I recently got a new, larger RX battery for my Raptor. I wanted a
heavier
> > one to add some nose weight as well as add electrical capacity. I ended
up
> > with a 2500mAh pack which fulfilled all the requirements.
> >
> > However it wasn't until the other day when I was cleaning the heli that
I
> > actually noticed what was written on one of the cells, they are 2500mAh
> > alright but they are NiMh and not NiCd. have been using the standard
Futaba
> > charger for the initial charge and two additional charges, will I be
> > damaging the cells or will this charger be acceptable too?
> >
> > Harry
>
> A NiCad trickle charger will charge NiMH cells without problems, though
due to
> the larger capacity, you will have to leave them on longer to get a full
> charge. If its a 100mA charger (typical) it will take 25 hours to charge a
> 2500mAH pack from flat........!
>
> --
> Pete
> christy@NOattglobalSPAM.net
> (make the obvious amendments to reply!)

[Boo]

Harry Spillett wrote:
> I recently got a new, larger RX battery for my Raptor. I wanted a heavier
> one to add some nose weight as well as add electrical capacity. I ended up
> with a 2500mAh pack which fulfilled all the requirements.
>
> However it wasn't until the other day when I was cleaning the heli that I
> actually noticed what was written on one of the cells, they are 2500mAh
> alright but they are NiMh and not NiCd. have been using the standard Futaba
> charger for the initial charge and two additional charges, will I be
> damaging the cells or will this charger be acceptable too?
>

I don't know what you mean by "standard Futaba charger" but if you mean
the wall-wart based thing that came with your TX then it will be most
unlikely to harm that battery by overcharging it, to say the least ;-)

Basically you want to charge a 2500 mAh NiMH battery at around 2.5A for
an hour (ish) if you are using a peak detect charger or alternatively at
say 250 mA for 10 hours using a constant current charger. I can't
remember what the charger Fuatba sell with their radio gear puts out but
I expect it would be around 100mA which would be a tad on the low side
for such a high capacity battery.


hth,

--
Boo

[david]

It'll be fine. NiMHs can be fast charged as well. To all intents and
porpoises you canb treat as NiCd.

D>

[Bill Wolff]

Hi Harry... Since the original Futaba charger is a trickle charger, I
wouldn't expect that you would have a problem. Although if you use a faster
charger, all bets are off. NiMh cells can get very hot from either too much
current or overcharging them longer than necessary. Rule of thumb is do not
allow the cells to reach no higher than 10 degrees above the air
temperature.

Bill


"Harry Spillett" <harry.spillett@bigfoot.com> wrote in message
news:bo03og$hpt$1@newsg4.svr.pol.co.uk on Date: Sat, 1 Nov 2003
11:00:30 -0000:

> I recently got a new, larger RX battery for my Raptor. I wanted a heavier
> one to add some nose weight as well as add electrical capacity. I ended up
> with a 2500mAh pack which fulfilled all the requirements.
>
> However it wasn't until the other day when I was cleaning the heli that I
> actually noticed what was written on one of the cells, they are 2500mAh
> alright but they are NiMh and not NiCd. have been using the standard
Futaba
> charger for the initial charge and two additional charges, will I be
> damaging the cells or will this charger be acceptable too?
>
> Harry



---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.536 / Virus Database: 331 - Release Date: 11/3/2003