BQ40Z80: Balance Time per mAh / Cell

LOIC REBOUSSIN

Expert 1620 points

Part Number: BQ40Z80

Hi,

I have many questions about to calculate the Balance Time per mAh cellx

What is the signification of "||" ?

RCVx, Rext and Rcb are in Ohms?

Vcell are in mV?

I've measured a 45% of duty cycle, should I use this value?

Best Regards,

Loïc

0 Batt over 6 years ago

Hi Loic,

The || indicates that the resistances are in parallel.

RVCx and other resistances are in Ohms

Vcell is in mV

Yes, 45% seems OK.

0 LOIC REBOUSSIN over 6 years ago in reply to Batt

Expert 1620 points

Hi Batt,

Can you confirm my result

Bat Time/mAh Cell 1 = 106 s/mAh

with parameters :

Vcell = 3600 mV

Rgs = 10 Ohms

RVCx = 1000 Ohms

Ratio = 45%

RExt = 100 Ohms

BR,

Loïc

0 Batt over 6 years ago in reply to LOIC REBOUSSIN

Hi Loic,

Please allow me another day to check this for you.

0 Batt over 6 years ago in reply to Batt

Hi Loic,

Please use a duty cycle of 54.4% for the bq40z80. The rest of the formula is correct.

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