









Version 1.1 Small LiPos 72813
MRF





Lipoly
Objective Performance Calculation Tool



Measured Cell IR =


< Enter cell measured internal
resistance here. If multicell pack,
use highest measured cell value



Cell Capacity =


< Enter cell
capacity in mAh units here



Figure of Merit (FOM) =


< Figure of
Merit (FOM). To be used as basis of
comparison to other packs and to track pack performance over time



Max. Current (A) =


< Maximum
recommended average current draw to prevent pack damage






Notes:



1. To use calculator, simply insert the
measured cell internal resistance and cell capacity in mAh into appropriate (green) cells.



To ensure highest
possible accuracy of results, cell IR must be taken when cell has been
allowed to settle at 72°F (22°C) for 1 hour minimum.



2. FOM = Figure of Merit. Figure of Merit is a calculation that uses
measured cell internal resistance and normalizes it to cell capacity. It is very useful when comparing packs of
different sizes and from different manufacturers. The larger the calculated FOM, the
better. For more background
information on FOM, go here: http://www.rcgroups.com/forums/showthread.php?t=1392662&page=1





3. Maximum recommended current draw is a
conservative calculation of maximum average current that one should stay
within to limit possibility of damage due to overheating during discharge. Use this value as an initial baseline and
adjust if you find that temperature is within a reasonable value in your
particular model. Recommended maximum
temperature for best longevity is no greater than 140 degrees F (60°C).






If you have some packs that have been evaluated using the tool
be sure to share them on the data thread
→

Database


There is a discussion
thread about this method of estimating a sensible maximum average current
here →

Discussion






Note that the display of
"True C" that was in an earlier
version of the tool has been removed as some people were
misinterpreting its significance.



You can easily calculate
an equivalent C value for the recommended maximum current by dividing that
current by the pack capacity in Amp Hours.






The Small LiPo Calculator
is identical to the normal Discharge Calculator except that it displays the
Maximum Current to 0.1Amp.

