EM1402EVM: Can this board charge 2 7S LiPo batteries in parallel?

Nicolas Montoya1

Part Number: EM1402EVM

Hello TI Forum,

So I am rather confused on the operation of this board. I read this discussion forum that states the EM1402EVM is not a charger but a cell balancer that balances each cell to 4.2V from the 12V supply; however, if each cell is balanced to 4.2V from a 12V supply, then how is it not a charger? Wouldn't the battery be fully charged if each cell has been balanced to 4.2V?

If it does balance each cell to 4.2V from a 12V supply, would it be possible to charge 2 7S LiPo Batteries in parallel by connecting all 14 cells to the EM1402EVM and putting a 12V input?

As I understand, LiPo charging involves a trickle charge phase,constant current phase, and then a constant voltage phase, so if this board only does cell balancing, than what voltage do the cells need to be in for this board to do active cell balancing?

Is there an all-in-on BMS solution that can charge 14 cells with active cell monitoring/bi-directional charging? If not, would I just need to add a battery charging IC to the battert stack while using this board simultaneously to balance the cells as they are charged?

Thanks!

over 6 years ago

0 Taylor Vogt over 6 years ago

TI__Genius 17370 points

Hi Nicolas,

Please refer to the following thread: https://e2e.ti.com/support/power-management/f/196/p/710160/2633817?tisearch=e2e-sitesearch&keymatch=EM1402%20Charge#2633817

This is not meant to be used as the sole charger, just as a form as balancing and controlling charge/discharge at certain times. However, yes cells in parallel are okay, as the series cells is the major limitation for the EVM. It is up to the user to decide the threshold at which to decide the balancing voltages and this can be manipulated using the example code.There is not an all in one solution that we offer but you may ask another question in this forum tagging a charger part and they can help provide support on picking the correct charger.

By the way, the link to the discussion forum you provided does not exist, please send another link.

Regards,

Taylor

0 Nicolas Montoya1 over 6 years ago in reply to Taylor Vogt

Prodigy 30 points

So in my case, the general process would be: use a separate charging IC board to perform the constant current and constant voltage phase on the whole battery stack (so it would charge the whole battery stack to 29.4V in my case, because there are 2 7S LiPo's in parallel), and then I would use the EV1402EVM to balance the cells once the whole battery stack has been charged? Or could i perform those tasks simultaneously?

Thanks!

0 Nicolas Montoya1 over 6 years ago in reply to Nicolas Montoya1

Prodigy 30 points

And here is the missing link: e2e.ti.com/.../2647311

0 Taylor Vogt over 6 years ago in reply to Nicolas Montoya1

TI__Genius 17370 points

Hi Nicolas,

Yes, your understanding is correct and you could do either way but typically charging is done while balancing.

Regards,

Taylor

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EM1402EVM: Can this board charge 2 7S LiPo batteries in parallel?