Battery values for all versions.

[CymatiCorp]

Epoc

if last_counter == 127
int(((Counter - 255) + 31) * 3.23))

Insight

if last_counter == 127
int(((counter - 245) +26) * 3.85)))

Epoc+

if contact[1] == 255
if contact[2] == 16
battery_percent = int( (((contact[17] - 117) +26) * 3.85) )

Where contact[1] is the counter
contact[2] is either 16 or 32, where 16 is for data, and 32 for gyro/mems
and then when the counter is 255
the 17th data value is the battery level.

at value 91 the battery is completely drained, and only is able to send off a couple packets
before the device shuts off.

I did a full charge of the Epoc+ then i turned it on for a second, and charged it again.
(To make sure the battery was topped off), and then plugged it in, and the highest value
was 117.

The Insight, i think may have topped out at 246, which, using the math i provided, would
give a value of 104% but it is only able to give that value for a few packets, so if we were
to use the correct value, it would probably almost never read it was actually at 100% and
over time, the battery would probably not charge to its complete potential anyways. so i'm
satisfied with it reading 104% for a second or two.

[CymatiCorp]

The Epoc+ also seemed to use this 17th data line for some other values...
while the counter is in the range of 0-254

I'm not entirely certain yet what they are used for yet.
However, they seemed to disappear entirely while the headset was experiencing
some activity, (ie movement+tapping sensors) so will have to look into this.