This will allow LiBCM to use 15 volt HVDCDC converters

Fans pull ~200 mA/each.

Drive Fans with QTY3 NFETs in series:

+15V
SGD NFET
SGD NFET
SGD NFET
FAN FAN FAN FLYBACK DIODE C145 C26 C20
CONTROL FET
GND

Add zero Ohm depop in case we get 12 volt supplies again

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Solution:

Added QTY3 NFETs between +12V (+15V) and existing circuit.

Done