> I need to parallel two battery packs to get one with a higher supply.
> These are lithium ion packs, 6 cells in series (so I'll end up with 12
> cells in total)

If you decide you need a zero drop diode equivalent you can use a
MOSFETs per battery,  with suitable control logic.

E&OE:

P channel MOSFET per battery
Source to B+.
Connect all drains as V+out.
Gates to ground to enable.
Light load to ground from Vout.
If Vout > Vbat turn off relevant FET
Differential is vv smal (<< 1V) so op amp needed.
Diiferential amp with say 2:1 divide allows high side sensing without
having B+ in common mode range.
Can do with high side N Channels but need gate drive > B+
Can do with low side N channels but messy sensing.
You can but zero gate drive FETs which AFAIR bias gates to zero point
with stored charge.

=A0Russell McMahon





















_apptech
Applied Technology

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