My NiCad battery gave up the ghost in my HT for the second time. They only
seem to last a few years, at the most. I was wondering if I replace the
NiCad's with newer NMHi batteries can I use the same charger? Both type
batteries are about 1.2 volts when charged. But I'm not sure about their
charging requirements.

Joel AG4QC

My NiCad battery gave up the ghost in my HT for the second time. They only
seem to last a few years, at the most.

Not uncommon. NiCd batteries _can_ have a fairly long service life
(up to 1000 charge/discharge cycles) if treated gently.

Unfortunately, in many applications they aren't treated gently...
they're run down all the way to zero (which tends to reverse-polarize
the weakest cells and damage them), and are recharged too rapidly
without proper charge management.

Even when treated very well, 1000 charge/discharge cycles wouldn't
last you more than 3 years if you run 'em down fairly far every
day, and recharge every night.

I was wondering if I replace the
NiCad's with newer NMHi batteries can I use the same charger? Both type
batteries are about 1.2 volts when charged. But I'm not sure about their
charging requirements.

In general, I believe that the answer is "maybe".

NiMH batteries can usually be trickle-charged using the same basic
method used for NiCd batteries. If your HT and its charger normally
required somewhere between 10 and 16 hours to fully recharge your
existing battery pack, then it'd probably work well enough for NiMH
batteries.

Fast-charging is a different issue, because the methods used to detect
"full charge, stop cramming!" on NiCd and NiMH batteries are somewhat
different. A fast-charge circuit originally designed for NiCd
batteries only, may end up damaging NiMH batteries.

Many of the aftermarket-batterypack companies which advertising in QST
etc. will either sell you a NiCd-based replacement pack, or a
NiNH-based pack with the option of buying a NiMH-aware fast charger.

--
Dave Platt AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

My NiCad battery gave up the ghost in my HT for the second time. They only
seem to last a few years, at the most.

Not uncommon. NiCd batteries _can_ have a fairly long service life
(up to 1000 charge/discharge cycles) if treated gently.

Unfortunately, in many applications they aren't treated gently...
they're run down all the way to zero (which tends to reverse-polarize
the weakest cells and damage them), and are recharged too rapidly
without proper charge management.

Even when treated very well, 1000 charge/discharge cycles wouldn't
last you more than 3 years if you run 'em down fairly far every
day, and recharge every night.

I was wondering if I replace the
NiCad's with newer NMHi batteries can I use the same charger? Both type
batteries are about 1.2 volts when charged. But I'm not sure about their
charging requirements.

In general, I believe that the answer is "maybe".

NiMH batteries can usually be trickle-charged using the same basic
method used for NiCd batteries. If your HT and its charger normally
required somewhere between 10 and 16 hours to fully recharge your
existing battery pack, then it'd probably work well enough for NiMH
batteries.

Fast-charging is a different issue, because the methods used to detect
"full charge, stop cramming!" on NiCd and NiMH batteries are somewhat
different. A fast-charge circuit originally designed for NiCd
batteries only, may end up damaging NiMH batteries.

Many of the aftermarket-batterypack companies which advertising in QST
etc. will either sell you a NiCd-based replacement pack, or a
NiNH-based pack with the option of buying a NiMH-aware fast charger.

--
Dave Platt AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

In article ,
says...

My NiCad battery gave up the ghost in my HT for the second time. They only
seem to last a few years, at the most. I was wondering if I replace the
NiCad's with newer NMHi batteries can I use the same charger? Both type
batteries are about 1.2 volts when charged. But I'm not sure about their
charging requirements.

I seem to recall that NiMH batteries can use the same chargers as
NiCd. HOWEVER -- LiON batteries cannot.

I'm sure others will correct me if I screwed up. ;-)


--
Dr. Anton Squeegee, Director, Dutch Surrealist Plumbing Institute
(Known to some as Bruce Lane, KC7GR)
kyrrin a/t bluefeathertech d-o=t c&o&m
Motorola Radio Programming & Service Available -
http://www.bluefeathertech.com/rf.html
"Quando Omni Flunkus Moritati" (Red Green)

In article ,
says...

My NiCad battery gave up the ghost in my HT for the second time. They only
seem to last a few years, at the most. I was wondering if I replace the
NiCad's with newer NMHi batteries can I use the same charger? Both type
batteries are about 1.2 volts when charged. But I'm not sure about their
charging requirements.

I seem to recall that NiMH batteries can use the same chargers as
NiCd. HOWEVER -- LiON batteries cannot.

I'm sure others will correct me if I screwed up. ;-)


--
Dr. Anton Squeegee, Director, Dutch Surrealist Plumbing Institute
(Known to some as Bruce Lane, KC7GR)
kyrrin a/t bluefeathertech d-o=t c&o&m
Motorola Radio Programming & Service Available -
http://www.bluefeathertech.com/rf.html
"Quando Omni Flunkus Moritati" (Red Green)

Dr. A.T. Squeegee wrote:
In article ,
says...


My NiCad battery gave up the ghost in my HT for the second time. They only
seem to last a few years, at the most. I was wondering if I replace the
NiCad's with newer NMHi batteries can I use the same charger? Both type
batteries are about 1.2 volts when charged. But I'm not sure about their
charging requirements.


I seem to recall that NiMH batteries can use the same chargers as
NiCd. HOWEVER -- LiON batteries cannot.

I'm sure others will correct me if I screwed up. ;-)



Some of those battery packs have more than 2 contacts, I think the
reason might
be extra internal compoenents that help detect when the charger should
shut down.
A NMHi battery pack made to replace a NiCd for a specific radio might
have the
correct network in it to work with the original charger.

Dr. A.T. Squeegee wrote:
In article ,
says...


My NiCad battery gave up the ghost in my HT for the second time. They only
seem to last a few years, at the most. I was wondering if I replace the
NiCad's with newer NMHi batteries can I use the same charger? Both type
batteries are about 1.2 volts when charged. But I'm not sure about their
charging requirements.


I seem to recall that NiMH batteries can use the same chargers as
NiCd. HOWEVER -- LiON batteries cannot.

I'm sure others will correct me if I screwed up. ;-)



Some of those battery packs have more than 2 contacts, I think the
reason might
be extra internal compoenents that help detect when the charger should
shut down.
A NMHi battery pack made to replace a NiCd for a specific radio might
have the
correct network in it to work with the original charger.

On Thu, 11 Dec 2003 23:10:56 GMT, Joel hath writ:
My NiCad battery gave up the ghost in my HT for the second time. They only
seem to last a few years, at the most. I was wondering if I replace the
NiCad's with newer NMHi batteries can I use the same charger? Both type
batteries are about 1.2 volts when charged. But I'm not sure about their
charging requirements.

In addition to the other postings here, do a Google groups
search on "nmhi" , or "battery" over in

rec.photo.digital

Those folks talk incessantly about using NMHi batteries. And,
due to their intense need for good battery service life, there
are some pretty knowledgeable folks there with suggestions.
As well, there'll be some refereneces to web sites with
beau coup technical talk on using NMHi batteries.

HTH
73
Jonesy
--
| Marvin L Jones | jonz | W3DHJ | OS/2
| Gunnison, Colorado | @ | Jonesy | linux __
| 7,703' -- 2,345m | config.com | DM68mn SK

On Thu, 11 Dec 2003 23:10:56 GMT, Joel hath writ:
My NiCad battery gave up the ghost in my HT for the second time. They only
seem to last a few years, at the most. I was wondering if I replace the
NiCad's with newer NMHi batteries can I use the same charger? Both type
batteries are about 1.2 volts when charged. But I'm not sure about their
charging requirements.

In addition to the other postings here, do a Google groups
search on "nmhi" , or "battery" over in

rec.photo.digital

Those folks talk incessantly about using NMHi batteries. And,
due to their intense need for good battery service life, there
are some pretty knowledgeable folks there with suggestions.
As well, there'll be some refereneces to web sites with
beau coup technical talk on using NMHi batteries.

HTH
73
Jonesy
--
| Marvin L Jones | jonz | W3DHJ | OS/2
| Gunnison, Colorado | @ | Jonesy | linux __
| 7,703' -- 2,345m | config.com | DM68mn SK

Joel wrote:
My NiCad battery gave up the ghost in my HT for the second time. They
only seem to last a few years, at the most. I was wondering if I
replace the NiCad's with newer NMHi batteries can I use the same
charger? Both type batteries are about 1.2 volts when charged. But
I'm not sure about their charging requirements.

Take a look at Isidor Buchmann's excellent articles at
http://www.buchmann.ca/
Takes a bit of time to study, but will answer 99% of your battery-related
questions.