Reverse polarity protection for a Li-Ion charger module

Main project requirements and background

The TP4056 charger module used in this project has no protection against reverse battery connection. Reversing the battery polarity can damage the charging IC.
A protection board is needed for a charger built around an integrated module containing six TP4056 ICs.

This circuit was developed to protect a multichannel charger module in which six TP4056 charging channels are combined into one compact unit. A separate protection module was built for each of the six outputs.
With the battery connected with correct polarity, the PNP transistor BC557B turns on the N-channel MOSFET IRF3205, completing the circuit between the charger on the left side of the schematic and the battery on the right.
The N-channel MOSFET IRF3205 was selected for its low on-resistance: RDS(on) up to 8mOhm at VGS=10V. VGS(th)=2-4V indicates only the threshold at which conduction begins and is not the gate voltage for fully turning on the MOSFET. The datasheet does not guarantee RDS(on)=8mOhm at VGS around 4V.
The 1N4007 diode limits the reverse voltage between the base and emitter of the PNP transistor BC557B, protecting the base-emitter junction from breakdown.
If the battery is connected with reversed polarity, the charging circuit is opened, while the indicator LED is powered and lights up.

A list of components used in this project, with links, is available in the Google document ("6xTP4056 reverse polarity protection" sheet).