I have been trying to charge my 2600 mah li-ion battery with this TP4056 protection module.

1) We have designed our pcb like
input 5v , 65ma through solar.

2) Output BAT+ and BAT- battery then

3) Output+ and Output- given to the circuit through a regulator.

4) I have shorted Bat- and Output- due to some reasons.

5) Where i have failed. It is not charging at all. Where is the issue Please help me with this. I am in very critical situation to handle this issue.

 

It sounds like you are feeding the 5V from the solar panel to a regulator?? And you wrongly believe that a 5V regulator with a 5V input works??
The datasheet of the TP4056 shows the Bat- connected to the circuit ground which is also the input ground.
We must see your schematic with a part number of the regulator.

 

Hi audioguru,

Thank you for your response. I have a doubt here why you want to know about the regulator. Okay i have used MCP1700.

 

The MCP1700 voltage regulator does not work when its input voltage is less than about +5.35V. Its maximum allowed input is only +6.5V.
Your solar panel output voltage might always be less than 5V or might be more than 6.5V so the regulator will not work or be blown up.

Why do you have a voltage regulator? The TP4056 charger IC uses an input up to +8V.

Why didn't you post your schematic?

 

The MCP1700 voltage regulator does not work when its input voltage is less than about +5.35V. Its maximum allowed input is only +6.5V.
Your solar panel output voltage might always be less than 5V or might be more than 6.5V so the regulator will not work or be blown up.

Why do you have a voltage regulator? The TP4056 charger IC uses an input up to +8V.

Why didn't you post your schematic?

Tomorrow morning i will share the schematic as i have to reach the office to send it. As per the MCP1700 datasheet the input operating range is from 2.3v to 6v. So i think we don't need to worry about it. My question is what happens if i short both Out- and Bat-.will it charge?

 

The MCP1700 never boosts the voltage. Instead it has a low dropout voltage so its input must be 5.35V or more for a regulated 5V output. If the input is 2.3V then its regulated output is 1.2V or less, but might be 0V if it is set for a 5V output.

Your charger IC needs 5V to 8V on its input. It probably does not charge the battery if its input is less than 5V. It does not need a voltage regulator but instead it might need a zener diode if the input ever goes higher than 8V.

The schematic on the datasheet of the charger IC already shows the Bat- connected to the In- and everything else that is grounded.

 

The MCP1700 never boosts the voltage. Instead it has a low dropout voltage so its input must be 5.35V or more for a regulated 5V output. If the input is 2.3V then its regulated output is 1.2V or less, but might be 0V if it is set for a 5V output.

Your charger IC needs 5V to 8V on its input. It probably does not charge the battery if its input is less than 5V. It does not need a voltage regulator but instead it might need a zener diode if the input ever goes higher than 8V.

The schematic on the datasheet of the charger IC already shows the Bat- connected to the In- and everything else that is grounded.

Thank youAudioguru for your info but here i am using mcp1700 is 3.3v regulated output and it is not for the charging IC. it is for the load circuit.
solar --> tp4056 --> battery ---> regulator ---> load circuit.

Why i am using regulator here because my whole circuit works on 3.3v but the battery max. is 4.1v just for regulating the battery voltage i am using regulator not for the tp4056. When i am testing with li-po battery with out load it is charging.


https://hallroad.org/product/3-7v-l...a-with-battery-protection-tp4056-in-pakistan/

In the above link they said (In "Using the module" )it is important to remove the load when charging. I am very confused because As per my design in my pcb the load is connected when it is charging.

 

Now you say the loaded MCP1700 voltage regulator is 3.3V and is draining some or all charging current from the TP4056 so the battery is not charging.
The input to the voltage regulator needs an automatic switch so that its input is the solar when there is sunlight and its input is switched to the battery when there is no sunlight.

The voltage regulator will not work when the battery voltage has dropped as it runs down. The amount of voltage needed at the input of the voltage regulator depends on how much current it must provide but you never said how much is the current.

 

Yep, I need to do that switching for mcp between solar and battery but i never did. Coming to the load current is it should produce is 35ma. I am just doing communication between xbee and pic controller. So min is 35ma.