Cutoff Load while charging the Lipo battery

[Johnny1010]

I want to cutoff the battery from load, while charging it. Schematic of the designed circuit is attached. I have used a PNP transistor to do it. Positive terminal of the battery is connected to emitter, charger positive input is connected to base. Simulation is running good but I want to know would this circuit work in hardware? Is there any problem with the circuit?

 

[MikeMl]

I cant see how this will stop charging the battery until the voltage reaches 5V-(forward drop of a Schottky diode) or about 4.8V.

Unless I dont understand where you are connecting the battery, your circuit simplifies to this:

 

[Johnny1010]

Charger positive input which is connected to base is basically the output of TP4056 ( https://dlnmh9ip6v2uc.cloudfront.net/datasheets/Prototyping/TP4056.pdf ), which will control the charging of the battery. And base would be pulled down to ground when charger is not plugged in, making the PNP transistor in active mode, hence load will be connected to battery in this condition.

 

[audioguru]

The problem with your original schematic is that it says "Charger Value= 5V" which is WRONG. It should say "Charger for single Lithium battery cell".

 

[eTech]

Hi

Try an logic level N mosfet.
Connect G to IC Charge pin. S to GND. Load between +V and D.
When charging starts, mosfet shuts off and disconnects the load.
When charging stops, mosfet turns on and connects the load.

If not already using the charge pin to light LED, PU thru 47k resistor to +V.