iPower battery cold charging test

To the Group:
Glen Trew, a week ago or so, made a good suggestion of checking an
iPower system at low temperatures to see if it affected the charging
of the battery. We had done tests previously that concluded the
battery itself did very well at low temperatures and much better than
alkaline batteries. Here's the test results done by Allan Watson, our
official PITA at Lectro (I kid thee not.)

AL used a 500 mAh iPower battery that had been charged and discharged
about 10 times in other experiments around here. He discharged the
battery and then recharged it until the green light came on (about one
hour) and then ran it down in an LM transmitter. The LM is a little
lighter load than the UM400 transmitters. The battery lasted 5:12.

He then put the discharged battery and the charger in a cold chamber
for 1 hour until everything got down to 40 F. He then put the cold
battery into the cold charger, powered it up and charged it until the
green light came on which was 15 minutes longer than at room
temperature, 1 hour and 15 minutes (1:15). He then removed the battery
from the charger and let the charged battery warm up to room
temperature for 20 minutes. This time it ran the LM for 4:19. The
ratio is 0.83 or 83% of the room temperature charging value. A 17%
reduction is not bad. We didn't try charging the battery longer in the
cold though it might have charged a little more. Frankly, it seemed
pretty good as it was. The reason we did 40F (4.4 C) was that we
figured a mixer could find a place that was at least that warm if they
had power available to charge the battery. (After all they could use a
UCR200 as a warming pad.)
Best Regards,
Larry Fisher
Lectrosonics

Larry,

Thanks for the testing. I'm curious what the run time would be if you
discharged the battery in the 40 degree temp. instead of bringing it
to room temp?

Stacy Brownrigg, CAS

On Feb 6, 10:15 am, Larry Fisher <lectroson....DeleteThis@gmail.com> wrote:
> To the Group:

> He then put the discharged battery and the charger in a cold chamber
> for 1 hour until everything got down to 40 F. He then put the cold
> battery into the cold charger, powered it up and charged it until the
> green light came on which was 15 minutes longer than at room
> temperature, 1 hour and 15 minutes (1:15). He then removed the battery
> from the charger and let the charged battery warm up to room
> temperature for 20 minutes. This time it ran the LM for 4:19. The
> ratio is 0.83 or 83% of the room temperature charging value. A 17%
> reduction is not bad. We didn't try charging the battery longer in the
> cold though it might have charged a little more. Frankly, it seemed
> pretty good as it was. The reason we did 40F (4.4 C) was that we
> figured a mixer could find a place that was at least that warm if they
> had power available to charge the battery. (After all they could use a
> UCR200 as a warming pad.)
> Best Regards,
> Larry Fisher
> Lectrosonics