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Konion  lithium ion cells
 
In Q&EFI magazine, May 04, Bob Smith reports his discharge test on a 3S 2P pack.

Bob's data is listed here, but altered to "per cell".

constant current             10 A

discharge time               6.9 minutes

discharge capacity           69 AM   [=1155mAh]

average EMF                    3.2V  [extracted from graph]

weight                            41g

I have used the above data to produce some interesting numbers.

discharge energy = 69AM * 3.2V = 221WM  [per cell]

average power = 221WM / 6.9M = 32W  [per cell]

average power/weight = 32W / 41g = .78W/g = 353W/lb

energy/weight = 221WM /41g = 5.4WM/g

The supplier claims a max continuous discharge current of 13A. This would increase the power/weight to about 400W/lb.

To obtain a "battery power/model weight" of 100W/lb the battery weight would be 25% of the model all-up weight.

The parameters "power/weight" and "energy/weight" apply to any number of cells, and to any pack configuration, and for any cell voltage. These are the most meaningful parameters to use when comparing cells.

"energy/weight" is an understandable name for what is usually referred to, enigmatically, as "energy density".

Abbreviations:

M          minutes

AM        amp minutes

WM       watt minutes

WM/g    watt minutes per gram

WM/lb   watt minutes per pound

W/g      watts per gram

W/lb     watts per pound