F
Franc Zabkar
Guest
I recently purchased two new Ericsson A2618s mobile phones that may
have been sitting on the shelf for up to a year. Needless to say, the
3.6V 750mAh NiMH battery packs (p/n BSC-11) had expired on the shelf
and were measuring only 2.0V. An overnight charge failed to recover
either battery pack. Further investigation revealed that neither phone
had made an attempt to charge these expired batteries, which suggests
to me that the A2618s has an intelligent charging system that avoids
batteries which it considers to be dead. After verifying that both
phones and both chargers would correctly charge a known good battery
pack, I returned the phones and batteries to Ericsson's service rep
(Fonebiz). Some three weeks later I received two replacement
batteries, still in their sealed packages. Unfortunately, these too
were old stock (2.0V) and once again failed to charge. :-( This time I
constructed a jig out of an old cable harness, a 39 ohm series
resistor, and a regulated 4.5VDC supply. After charging for a few
hours, I installed the battery packs in the phones and was rewarded
with proper charging behaviour. Unfortunately I have since discovered
that even after several charge/discharge cycles, neither battery pack
approaches the claimed 110 hour standby capacity. The closest is
around 40 hours.
Am I correct in assuming that the phone's charging system analyses the
state of the battery and refuses to charge it if its voltage is too
low? Ericsson customer service was unable to answer this question.
The battery packs have three pins, red (+), black (-), and blue. The
blue and black wires appear to be tied together. Does anyone know the
function of the blue wire? Is it used to differentiate between NiMH
packs amd Li-Ion packs (p/n BHC-11)? Does it connect to a thermal
cutout?
- Franc Zabkar
--
Please remove one 's' from my address when replying by email.
have been sitting on the shelf for up to a year. Needless to say, the
3.6V 750mAh NiMH battery packs (p/n BSC-11) had expired on the shelf
and were measuring only 2.0V. An overnight charge failed to recover
either battery pack. Further investigation revealed that neither phone
had made an attempt to charge these expired batteries, which suggests
to me that the A2618s has an intelligent charging system that avoids
batteries which it considers to be dead. After verifying that both
phones and both chargers would correctly charge a known good battery
pack, I returned the phones and batteries to Ericsson's service rep
(Fonebiz). Some three weeks later I received two replacement
batteries, still in their sealed packages. Unfortunately, these too
were old stock (2.0V) and once again failed to charge. :-( This time I
constructed a jig out of an old cable harness, a 39 ohm series
resistor, and a regulated 4.5VDC supply. After charging for a few
hours, I installed the battery packs in the phones and was rewarded
with proper charging behaviour. Unfortunately I have since discovered
that even after several charge/discharge cycles, neither battery pack
approaches the claimed 110 hour standby capacity. The closest is
around 40 hours.
Am I correct in assuming that the phone's charging system analyses the
state of the battery and refuses to charge it if its voltage is too
low? Ericsson customer service was unable to answer this question.
The battery packs have three pins, red (+), black (-), and blue. The
blue and black wires appear to be tied together. Does anyone know the
function of the blue wire? Is it used to differentiate between NiMH
packs amd Li-Ion packs (p/n BHC-11)? Does it connect to a thermal
cutout?
- Franc Zabkar
--
Please remove one 's' from my address when replying by email.