NIMH Batteries

Paul, Have you been using one in your plane ?

Goodness no, I can't even afford anything that draws high power, let
alone one of these bad boys to juice it. I myself am going to wait for
prices to come down a little bit first, and until then just deal with
the extra few pounds of lead in my current brick. It'd sure be swell
though...

-Paul

At 22:55 04 December 2008, Andy wrote:
On Dec 4, 3:21=A0pm, Martin Gregorie
wrote:
Slightly hijacking this thread:

Can anybody recommend a reliable manufacturer of NiMH batteries.

I've tried a variety of makes of 2 - 2.4 Ah AA cells for running
digital
cameras and have to say I'm far from impressed.

My experience with NiMH in digital cameras is similar. I have gone
back to using disposable alkaline cells in my DSLR.

Andy


Regarding NiMH batts for digital cameras, I have been involved in soaring
and photography for about 40 years. Two years ago I wanted a small but
capable digital camera and, after much research, decided to go with a
Canon Powershot S3 IS. But, this is not about the camera. I wanted long
lasting, reliable power for the camera so I did quite a bit of research on
the best batteries and charger to use. I found Maha Energy Corp in La
Verne, CA and bought one of their MH-204W chargers and 4 of their AA
2300mAH Powerex NiMH batteries. The (international) charger is a real key
in that it is able to charge the batteries to 99% of their rated power,
something most chargers cannot do. I have been extremely satisified with
the performance of these products over the past two years. Here is the
Maha website address:

http://www.mahaenergy.com/store/Index.asp

They now have Powerex batteries that are 2700mAH. Be sure to read the
details on what the MH-C204W charger can do...it's impressive.

James Hamilton
Reno, NV

On Dec 4, 3:21*pm, Martin Gregorie
wrote:
Slightly hijacking this thread:

Can anybody recommend a reliable manufacturer of NiMH batteries.

I've tried a variety of makes of 2 - 2.4 Ah AA cells for running digital
cameras and have to say I'm far from impressed.

I have two good chargers (a Vencon which is mains driven and controlled
by a PC and a Pro-Peak Prodigy II which runs off 12v and designed for
field charging RC aircraft batteries). Both are peak chargers and can *
record the mAh during charge and test discharge.

I never have had your problem Martin.

Abusing 7 cell 1700 and 1900 mAh, NiMH packs in electric sailplanes
(F5J), fast charging them at contests(up to 5 amps) and running them
at 50--60 amps for 40 seconds, they always lasted as well as the
NiCds, I used prior. I have a Triton charger, that records charge
rates and capacities. I would put my packs through several charge
discharge cycles once a week or so. One problem with NiMH batteries is
that they discharge faster than NiCds if left laying around. I did not
use blister pack batteries found in retail electronic shops though.



I've yet to try a NiMH brand that comes near its rated capacity.
Most
show an, ahem, spectacular drop in capacity during subsequent cycles.

I've never had any of this nonsense from NiCd cells: they 'just
work' (unless made by GP).

Bottom line: unless I can find a brand of NiMH that does what it says on
the tin there's no way I'm going to spend good money on using them to
replace SLAs *or trust them to last out a decent xc flight.

--
martin@ * | Martin Gregorie
gregorie. | Essex, UK
org * * * |

Also check out the NiMH packs at
http://www.all-battery.com/rectangul...customize.aspx.
This is a 14.4 volt 10 AH pack with a flat discharge rate. It weighs
about 2/3's of the typical 12 volt 7/8 AH sealed lead acid battery
used in most gliders. It's rated for 500 recharge cycles. You can also
but individual cells and make your own pack to what ever specs you
need.

Charlie

I´ve been using a pack of LiFeP cells for 2 years now and won´t go back to
SLA. (20 x A123 in 4s/5p)
http://a123systems.textdriven.com/pr...UGUST_2008.pdf

Michael

"K M" schrieb im Newsbeitrag
...
On Dec 4, 12:45 pm, sisu1a wrote:


40 amp/hr is $800 (U1-12XP, their battery which is the same size as a
12v 12 amp/hr lead brick but half the weight)
24 amp/hr is $600 ( U1-12RTL, same size/weight as above but with
built in battery management system)
Both series are claimed to be able to be charged on most standard lead
acid chargers (set for AGM/GEL cells)

-Paul

Paul, thanks for the links, I never knew these existed . If one can
actually get "Thousands of cycles" then these would be much more
affordable than the steep initial cost might sugest. Have you been
using one in your plane ?
Thanks

Hi,

You can also try this link for Li batteries
http://glider-equipment.nl/catalog/p...roducts_id=104
.. Maybe someone has already used tthem, and can give us advice.

Regars,
Pedro asw 27

On 4 dic, 20:45, sisu1a wrote:
*I dont mind using the sealed lead

acid batteries but the NIMH has many advantages . And yea, I know
price isnt one of them.
Thanks

NIMH?!? If cost doesn't frighten you, then why not LiFePO4?http://www.valence.com/products/batt...es/u-charge_rt
(integrated battery maintenance version...)http://www.valence.com/sites/all/the...Charge%20RT%20...
Kick a$$ batteries with 1/4-20 threaded connections to boot...but
certainly not cheap. Just talked to a nice lady there at Valence, and
for reference:

*40 amp/hr is $800 (U1-12XP, their battery which is the same size as a
12v 12 amp/hr lead brick but half the weight)
*24 amp/hr is $600 ( U1-12RTL, same size/weight as above but with
built in battery management system)
Both series are claimed to be able to be charged on most standard lead
acid chargers (set for AGM/GEL cells)

-Paul

On Thu, 04 Dec 2008 23:50:59 +0000, Tim Newport-Peace wrote:


Forget NiCD Martin. They will soon become unobtainable in Europe because
EU directive 2006/66/EC Article 4 (and others) prohibits 'The placing on
the market of portable batteries or accumulators, including those
incorporated into appliances, that contain more than 0,002 % of cadmium
by weight.

I know it! Pity, because they were reliable, bullet-proof batteries: I
used them to run the d/t timer on Free Flight models where reliability is
all: only 99% reliability = guaranteed model lost upwards.

NiMH has inferior cold weather performance to NiCd as well.


Just remember that (in Europe) changing the primary electrical source is
a Mod requiring a raft of EASA paperwork!

Interesting, so replacing SLA with the NiMH drop-ins advertised in S&G
will cause a paper blizzard.


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |

On Thu, 04 Dec 2008 17:18:17 -0800, Mike wrote:

Abusing 7 cell 1700 and 1900 mAh, NiMH packs in electric sailplanes
(F5J), fast charging them at contests(up to 5 amps) and running them at
50--60 amps for 40 seconds, they always lasted as well as the NiCds, I
used prior. I have a Triton charger, that records charge rates and
capacities. I would put my packs through several charge discharge
cycles once a week or so. One problem with NiMH batteries is that they
discharge faster than NiCds if left laying around. I did not use blister
pack batteries found in retail electronic shops though.

Care to mention a brand name?

The best results I've had were with Vansons. They also died after 10
cycles or so, but that could well have been due to a crappy Chinese
charger I unwisely bought from Maplin.


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |

On Thu, 4 Dec 2008 17:18:17 -0800 (PST), Mike
wrote:

One problem with NiMH batteries is
that they discharge faster than NiCds if left laying around. I did not
use blister pack batteries found in retail electronic shops though.

Not all of them. A few have fixed the auto-discharge problem.
In Europe, commercial names a

Uniross Hybrio
Sanyo Eneloop
Sony Cycle Energy

Aldo Cernezzi

On Dec 5, 8:05*am, Martin Gregorie
wrote:
On Thu, 04 Dec 2008 17:18:17 -0800, Mike wrote:
Abusing 7 cell 1700 and 1900 mAh, NiMH packs in electric sailplanes
(F5J), fast charging them at contests(up to 5 amps) and running them at
50--60 amps for 40 seconds, they always lasted as well as the NiCds, I
used prior. I have a Triton charger, that records charge rates and
capacities. *I would put my packs through several charge discharge
cycles once a week or so. One problem with NiMH batteries is that they
discharge faster than NiCds if left laying around. I did not use blister
pack batteries found in retail electronic shops though.

Care to mention a brand name?

Martin,

I purchased my batteries here;

http://www.battlepack.com/NICAD-Battlepacks.asp

I do not see the batteries I purchased listed anymore. They were
"Zapped" 1700 and 1900 mAh 7cell packs. I think they were HR 1700 and
HR 1900 cells, but I do not recall the manufacture-it was five years
ago . The packs are in heatshrink, and I do not want to peel it off.
Any of the NiMH cells or packs currently sold by Battlepack would have
equal or better performance. They are higher capacity than when I was
buying them.

I have not flown RC for about four or five years, but after about two
year I recharged the packs and after a few charge/discharge cycles
they would charge up to the stated capacities.

Mike






The best results I've had were with Vansons. They also died after 10
cycles or so, but that could well have been due to a crappy Chinese
charger I unwisely bought from Maplin.

--
martin@ * | Martin Gregorie
gregorie. | Essex, UK
org * * * |