BQ24750: Estimating runtime in varying (temperature) conditions

MMx

Part Number: BQ24750
Other Parts Discussed in Thread: BQ40Z80, BQ34Z100-G1

Is any of the SMBus enabled chargers able to give a (more or less accurate) estimate on the remaining battery capacity taking into account the current temperature?

Our system is going to be used in various environments from -20 to +65 °C.

It is my understanding that the SMBus command AtRateTimeToEmpty() only takes into account a hypothetical current value but there is no way for the battery itself to calculate the temperature into that. Are chargers available that can do just that?

over 4 years ago

0 Angelo Zhang87 over 4 years ago

TI__Genius 11850 points

Hi,

No, we don’t have a charger that can do this. I have forwarded your question to the gauge team so they can provide further input.

Best regards,

Angelo

0 Andy Liu (BMS) over 4 years ago

TI__Guru 52115 points

What is your application? Single-cell or multi-cell? The gauge device takes the temperature into consideration when calculating the remaining capacity.

In addition, I would suggest you check if the battery used in your system can handle -20C to 65C well. -20C is a bit challenging for most batteries. Quite a few perform poorly at -20C.

Andy

0 MMx over 4 years ago in reply to Andy Liu (BMS)

Intellectual 300 points

Our system will probably use 4-6 cells in series.

0 Andy Liu (BMS) over 4 years ago in reply to MMx

TI__Guru 52115 points

I would suggest you take a look at the following gauge devices.

a) BQ40z50-R3

b) BQ40z80

c) BQ34z100-G1

Andy

Power management

Power management forum

BQ24750: Estimating runtime in varying (temperature) conditions