Li-Ion battery charging with reverse battery polarity protection

[maxpayne]

This is my first project based post. I have designed a li-ion battery charging circuit with reverse battery polarity protection for both charger and load. The design is such that, it can protect both BQ24090 and outer load (between LOAD+ and LOAD-) while battery, BAT1 is connected reverse. I dont have the parts right now to test a prototype, so I have posted the circuit here for your valuable critics, whether the design is ok or wrong in any point. Note that there is a low voltage cutoff circuit which is controlled by LTC1998 with cutoff voltage 2.8V.

My design requirement is -

- Safely charge a single removable 14500 size Li-ion cell at 500 mA via USB
- Protect charger and load from reverse battery insertion (while charging and not charging)
- Disconnect battery from load below ~2.8v battery voltage
- No hidden lead parts (e.g., QFN)

[richcj10]

It may be easier to use just a P-mosfet for this. Depending on the mosfet, it will shut off after x volts

[maxpayne]

Can you describe elaborately how ?

[maxpayne]

My primary concern is to check if the reverse protection circuitry for both load and charging side design is ok or not ?

[HackedFridgeMagnet]

Having once blown my laptop by connecting it's USB to something non isolated. I would suggest an isolated charger.

You should be able to go through all the possible connection scenarios to work out what will happen in each case.
either on paper, or in LTSPice or breadboarding some old salvaged parts and ignoring the ICs.

Another way to do RP protection is a fuse and a Diode (maybe tvs) obviously this wont self reset but it gives over current protection too.