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Need4Speed
2009.12.07, 08:40 PM
I have 24 AA 750 Orion Batteries. How do I go about matching these batteries. Can some one post a detail description on how to match these batteries. Is it possible to use the MAHA Charger to match them.

Thanks.

EMU
2009.12.07, 09:31 PM
Fully charge the cells, then discharge them. Record the MAH of each cell. Then group them together. The cells should all have a similar capacity, which will mean that the pack will dump all at once, rather than a little at a time.

Use the low capacity packs for practice and qualifying, and the higher capacity packs for races.

There is much more to matching the packs than just the capacity, but that is a good starting point.

You can also get an idea for the internal resistance of the cell, and try to sub match internal resistance within the capacity matching. When you charge a cell in the MAHA Wizard One charger, it will give you a voltage readout. The first reading is the internal resistance as the cell is tested, then it will read the voltage of the cell as it is charging. The lower the resistance number is, the faster the cell will be.

With more advanced equipment, it takes less time to match the cells, and is much more accurate. However, its very expensive... I wouldnt focus too much on trying to match the cells, just try to weed out the poor performing cells. That is the most important part of trying to match the cells.

Need4Speed
2009.12.09, 10:54 PM
Thanks for the great post EMU. I have a few questions.

If I am going to match Orion 750's, What Amp should I charge them and what amp should I discharge them?

After I discharge the cell, should I pay any attention to voltage besides capacity?