> What's the best way to calculate battery life if boost converter is evolv=
ed.


Andre

The following may APPEAR o be "pedantic" - just picking at a small and
unimportant "mistake" but in fact in this case there are two possible
interpretations of what you wrote, which differ by a factor of1000,
and it is impossible to be sure which one you intend

You need to pay careful attention to your units so that we can be sure
we are all talking about the same thing.

Your answer could be interpreted as meaning

"about 200 hours"   which would be very very very  roughly correct.

"about 200000 hours" which would be very very very wrong.

Writing 200.000 is very misleading.
It implies either a prevision to 1/1000 of whatever unit you are using
(hours?) OR that the "." is being used as a 1000's separator  so that

   200.000  =3D 200,000    =3D =3D =3D  200.000

Because you have used 0.008 mA where your figures SUGGEST that either
8 mA or 0.008 A should have been used, it IS possible that you do
intend the incorrect figure of 200000 hours.

Please check your information provided and update so that we can be
sure of what you are saying.

____

as Bob notes.
Battery energy capacity / aberage energy use is a reasonable first try.
But ONLY a first try.

Per cell  average voltage AVAILABLE is about 1.15 Volt.
Battery voltage =3D 1.3 V average.
Available energy =3D 2.3 x 2000 mAh x 80% ~~~=3D 3680 mWh

IF load is 8 mA
IF Vload =3D 3V3.
IF boost efficiency ~~~=3D 80%

Power to converter =3D 8 x 3.3 x 1/80% =3D 33 mW

Battery life ~~~~=3D 3680 / 33 =3D 11.5 hours or about 1100 hours.
Or about 120
Or about 150
or ...
depending on other assumptions which can be discussed.

Amongst other things you use a figure of 80% for available battery energy.
That MAY have be the same as the 80% converter efficincy that I assumed.
If so then increase hours by 1/.8 =3D 1.25 x.
BUT using only 80% of battery capacity is wise.
But lets get the basics right first and hen we can discuss such details.

200.000 =3D 200 ?

or 200.000 =3D 200000 ?


          Russell
--=20
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