Solar cell battery charger

SANJAY ATTARA

Other Parts Discussed in Thread: BQ25883, BQ25798

Please suggest me appropriate IC part number to charge 2 cell 18650 Li-ion battery (2S X 2P) having 7.2 Volts/ 6.4 A by triple junction GaAs 2 solar cells in series having Voltage range from 2.92 Volts to 5.26 and current from 470mA to 510mA. I also want alternate charging using USB as well if possible. I am using BQ25883 for USB charging and LTC4121 step-down battery charger. Since my Solar cells voltage has changed from 11 volts to 5 volts I now need to replace it with boost charger.

over 2 years ago

0 Jeff F over 2 years ago

TI__Guru**** 166176 points

Hi Sanjay,

BQ25798 buck-boost charger has an MPPT feature that can be enabled via I2C host. Its min operating input voltage is 3.6V and max is 24V. It has MUXs to drive two sets of external back-to-back FETs for 2 different inputs.

Regards,

Jeff

0 SANJAY ATTARA over 2 years ago

Prodigy 30 points

Hello Jeff,

My PV Panel Vmpp range is 2.93V to 5.26V and Voc range is 4.18V to 6.35V. While BQ25798's minimum input voltage starts at 3.6V. Please suggest a solution.

0 Jeff F over 2 years ago in reply to SANJAY ATTARA

TI__Guru**** 166176 points

Hi Sanjay,

Unfortunately, TI battery charger team does not have a solution for this.

Regards,

Jeff

0 SANJAY ATTARA over 2 years ago in reply to Jeff F

Prodigy 30 points

Hi Jeff,

Thanks for your quick response. Please suggest appropriate solar cell power conditioner/dc-dc buck-boost converter/energy harvester solution to use before BQ25798.solar PV input.

0 Jeff F over 2 years ago in reply to SANJAY ATTARA

TI__Guru**** 166176 points

Hi Sanjay,

Unfortunately, TI does not have a solution for your application.

Regards,

Jeff

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Solar cell battery charger