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rajiex
2010.11.26, 08:34 PM
How long do batteries hold their form. I have seven sets of batteries that no longer peak any where near their orginial packaging. Is there a way to refresh their charge. I haave some 990s that now only peak at 550. Are they dead? I am using a MAHA 9000, I have tried discharging/charging to get a balance set. Am I wasting my time and just buy new batteries. What is the life expectency of these batteries. I usually only race once a week.

rensuchan
2010.11.26, 09:08 PM
I've been experimenting with refresh cycles and such as well over the past week since I just got my LaCrosse BC-700 on Monday.

How have you been running the refresh cycles? Are you using higher charge rates or trying to slow charge to refresh? I think the lower charge rates are better for trying to restore some life to the batteries.

But if they're down that much I'm not sure if there is a lot that can be done. Might be best to get some new sets and save those for practice batteries... I think I'll be doing the same myself soon :)

bermbuster
2010.11.27, 07:28 AM
How long do batteries hold their form. I have seven sets of batteries that no longer peak any where near their orginial packaging. Is there a way to refresh their charge. I haave some 990s that now only peak at 550. Are they dead? I am using a MAHA 9000, I have tried discharging/charging to get a balance set. Am I wasting my time and just buy new batteries. What is the life expectency of these batteries. I usually only race once a week.
while the mah is important you need to track voltages of each cell.

Do you have a high power discharger? You want to discharge at 3 amps....and one cell at a time not in a gang discharger....
(true amperage draw from a racing mini z) This will condition your cells like they are racing.

Now when you charge them( 1-3 amps...higher amps more punch...less life) see how much mah go in and what voltage they are peaking at 1.45 etc....try to group them....Do this a few times and see if they are getting better....staying the same or getting worse. reshuffle the matching of the cells. This way you can grade the cells and get rid of the non performing ones.
Remember your pack of 4 is only as good as the weakest cell......

rensuchan
2010.11.27, 10:22 AM
Do you have a high power discharger? You want to discharge at 3 amps....and one cell at a time not in a gang discharger....
(true amperage draw from a racing mini z) This will condition your cells like they are racing.

Do you have a discharger recommendation for this?

bermbuster
2010.11.27, 10:28 AM
Do you have a discharger recommendation for this?
a much more sub c or a novak smart tray.....
they were developed for sub c (1/10th) technology. They adjust (size) and will work awesome with aaa cells. You can find them used really cheap.
New ones are usually discounted as well....

rajiex
2010.11.27, 11:27 AM
Now I am more confused. Do you match batteries by peak voltage or MAH?

bermbuster
2010.11.28, 06:57 AM
Now I am more confused. Do you match batteries by peak voltage or MAH?

both....
higher voltage packs = more speed
higher mah packs= more runtime.

After a 5 minute main in stock you may use 200mah of power.
Your cells are 900(roughly). Technically you can get 3-5 minite races from one pack. The only thing with nimh batteries the voltage drops off as the pack discharges.....By having matched packs charged....then re-peaked before
a race will ensure the highest voltage with the power to last for 5 minutes or more of racing.

The idea of matching then utilizing a charging/discharging program
will ensure your batteries are flowing the most voltage and current to make your mini z perform its best.

rajiex
2010.11.28, 09:35 AM
both....
higher voltage packs = more speed
higher mah packs= more runtime.

The idea of matching then utilizing a charging/discharging program
will ensure your batteries are flowing the most voltage and current to make your mini z perform its best.

What is a good baseline to measure by. What is voltage is considered for practice and rack packs.