BQ2000: Charging 3s NiMH battery (1.2V each cell) and 3s Li-ion battery (1.5V each cell)

Rohit Naik

Part Number: BQ2000
Other Parts Discussed in Thread: BQ25172, BQ25171-Q1

Tool/software:

Hi Team,

I need to charge 3 cell NiMH battery (1.2V each cell) and 3 cell Li-ion battery (1.5V each cell). Can you please suggest a solution.

Thanks and regards

Rohit A Naik

2 months ago

0 Jeff F 2 months ago

TI__Guru**** 166596 points

Hi Rohit,

I recommend BQ25172.

Regards,

Jeff

0 Rohit Naik 2 months ago in reply to Jeff F

Prodigy 10 points

Hi Jeff

Greetings!!

The Voltage of 3 cell 1.5V in series will be 4.5V

according to datasheet the 3 cell charging voltage will be 1.33* 3 = 3.99V. How will it be able to charge the 1.5V battery

thanks and regards

Rohit A Naik

0 Jeff F 2 months ago in reply to Rohit Naik

TI__Guru**** 166596 points

Hi Rohit,

The BQ25171-Q1 is a better fit but it can only charge LiIon up to 4.35V.

Regards,

Jeff

0 Rohit Naik 1 month ago in reply to Jeff F

Prodigy 10 points

Hi Jeff,

Greetings!!

The datasheet of BQ25171-Q1 says 1-2 cell Li-Ion I need to charge 3 cell li-ion. Can you please clarify.

Thanks and regards

Rohit A Naik

+1 Jeff F 1 month ago in reply to Rohit Naik

TI__Guru**** 166596 points

Hi Rohit,

The 1-2 cell LiIon assumes each LiIon is 4.2V-4.35V. Your cells are 1.5V each, for a max of 4.5V. The BQ25171-Q1 can be set for a max charge voltage for 1-cell LiIon of 4.35V. If you want one IC to charge both NiMH and LiIon packs, this is the best choice. If you want 2 different chips, then you can choose from the BQ2517x family.

Regards,

Jeff

0 Rohit Naik 1 month ago in reply to Jeff F

Prodigy 10 points

Thank you for the support Jeff

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BQ2000: Charging 3s NiMH battery (1.2V each cell) and 3s Li-ion battery (1.5V each cell)