Forums

dead unused NiMH AA cells

Started by Adam Funk June 25, 2015
I recently opened a pack of NiMH AAs that I'd had lying around for a
while, & some of them wouldn't charge at all.  I tried putting them in
the fancy German charger as well (I can't remember the model name, but
it's the one that has discharge, test, & refresh modes) but it just
showed "null" for them, as if they weren't even there.

Is there some need to charge NiMH cells as soon as you buy them?
On Thu, 25 Jun 2015 20:42:36 +1000, Adam Funk <a24061@ducksburg.com> wrote:

> I recently opened a pack of NiMH AAs that I'd had lying around for a > while, & some of them wouldn't charge at all. I tried putting them in > the fancy German charger as well (I can't remember the model name, but > it's the one that has discharge, test, & refresh modes) but it just > showed "null" for them, as if they weren't even there. > > Is there some need to charge NiMH cells as soon as you buy them?
No, but NiMH do die even if unused. In my experience it takes 2-4 years for this to happen. Also some Chinese manufacturers produce cells that never work. The brand "BTY" is a standout in this category (BTY = "battery thought you - ha ha")

"David Eather"  wrote in message news:op.x0tdzaliwei6gd@phenom-pc.asus...

On Thu, 25 Jun 2015 20:42:36 +1000, Adam Funk <a24061@ducksburg.com> wrote:

> I recently opened a pack of NiMH AAs that I'd had lying around for a > while, & some of them wouldn't charge at all. I tried putting them in > the fancy German charger as well (I can't remember the model name, but > it's the one that has discharge, test, & refresh modes) but it just > showed "null" for them, as if they weren't even there. > > Is there some need to charge NiMH cells as soon as you buy them?
No, but NiMH do die even if unused. In my experience it takes 2-4 years for this to happen. Also some Chinese manufacturers produce cells that never work. The brand "BTY" is a standout in this category (BTY = "battery thought you - ha ha") *** Eneloop rechargeable NiMH batteries by Sanyo are very good at retaining their charge. Have had some still almost fully charged after a year, while other brands are dead in 2 or 3 months.
On Sat, 27 Jun 2015 09:12:13 +1000, "Larry" <larry17@gmail.com> wrote:

>Eneloop rechargeable NiMH batteries by Sanyo are very good at retaining >their charge.
I really like Eneloops. They are not available with solder tabs, so I bought myself a spot welder so that I can make all my batteries from Eneloops. I wish they were available in Sub-C size. From what I understand, Panasonic have now bought Eneloop.
> Have had some still almost fully charged after a year, while >other brands are dead in 2 or 3 months.
Other brands also have LSD (Low Self-Discharge) batteries. -- RoRo
On Sun, 28 Jun 2015 05:40:36 +1000, Robert Roland <fake@ddress.no> wrote:

> On Sat, 27 Jun 2015 09:12:13 +1000, "Larry" <larry17@gmail.com> wrote: > >> Eneloop rechargeable NiMH batteries by Sanyo are very good at retaining >> their charge. > > I really like Eneloops. They are not available with solder tabs, so I > bought myself a spot welder so that I can make all my batteries from > Eneloops. I wish they were available in Sub-C size. > > From what I understand, Panasonic have now bought Eneloop. > >> Have had some still almost fully charged after a year, while >> other brands are dead in 2 or 3 months. > > Other brands also have LSD (Low Self-Discharge) batteries.
The OP was asking about dead as in faulty batteries that could no longer take a charge
On 2015-06-27, David Eather wrote:

> On Sun, 28 Jun 2015 05:40:36 +1000, Robert Roland <fake@ddress.no> wrote: > >> On Sat, 27 Jun 2015 09:12:13 +1000, "Larry" <larry17@gmail.com> wrote: >> >>> Eneloop rechargeable NiMH batteries by Sanyo are very good at retaining >>> their charge. >> >> I really like Eneloops. They are not available with solder tabs, so I >> bought myself a spot welder so that I can make all my batteries from >> Eneloops. I wish they were available in Sub-C size. >> >> From what I understand, Panasonic have now bought Eneloop. >> >>> Have had some still almost fully charged after a year, while >>> other brands are dead in 2 or 3 months. >> >> Other brands also have LSD (Low Self-Discharge) batteries. > > The OP was asking about dead as in faulty batteries that could no longer > take a charge
Right: they've never been charged (I just opened the package) & they are "pre-dead". -- There's nothing in Scripture that forbids letting our lawn go wild. --- Garrison Keillor
On 2015-06-26, David Eather wrote:

> On Thu, 25 Jun 2015 20:42:36 +1000, Adam Funk <a24061@ducksburg.com> wrote: > >> I recently opened a pack of NiMH AAs that I'd had lying around for a >> while, & some of them wouldn't charge at all. I tried putting them in >> the fancy German charger as well (I can't remember the model name, but >> it's the one that has discharge, test, & refresh modes) but it just >> showed "null" for them, as if they weren't even there. >> >> Is there some need to charge NiMH cells as soon as you buy them? > > No, but NiMH do die even if unused. In my experience it takes 2-4 years > for this to happen. > > Also some Chinese manufacturers produce cells that never work. The brand > "BTY" is a standout in this category (BTY = "battery thought you - ha ha")
These were Maplin's own brand --- first time I've had a problem with them, but you never know if they're all coming from the same place. -- A life is like a garden. Perfect moments can be had, but not preserved, except in memory. LLAP. --- Leonard Nimoy