Competition Electronics Turbo35-GFX User Manual page 20

reason for this is the fact that cell capacities have increased. Another reason is that R/C
motors these days draw a lot of current, so it takes a higher discharge rate to emulate
these high currents.
The discharge function is the main tool that you use to compare cell performance. You
can discharge a cell or a pack to a defined cutoff voltage at a fixed current and observe
the discharge voltage over time as a graph, as well as time the discharge duration.
Obviously, a rather simple application of this, and one that is used most frequently, is to
run the identical discharge procedure on several similar packs and compare the results.
More run time is better, of course, but a higher output voltage is better, as well.
Cell Matching and it's Effects
For the best performance, you'll want to obtain what is known as a matched pack. This
means that the cells in the pack have similar discharge profiles. This is desirable because
cells with similar discharge times and similar discharge profiles will tend to deliver
similar output power over the same time period. They will reach the end of their power
output at the same time. Matching prevents the condition where some cells in a pack are
still delivering current to the load while others are fully discharged.
Figure 10. TurboMatcher 4/35.
As we have already stated, individual cells vary widely, both in output voltage and
discharge, or run time. Cell matching companies go through many cases of batteries in
order to separate out the best ones, and match them into packs for top racers. The lesser
quality cells are also matched into packs, but they are sold for less money. Most matcher
companies use the CEI TurboMatcher 4 (a special charger/discharger that is designed to
grade 4 single cells at a time) to test cells and match them.
You can do the same thing with a T35-GFX; the only difference is that you will have to
do one cell at a time.
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