▓How to increase the amperage of the tp4056 module to 3A?▓

[electronium]

Greetings to the colleagues of the forum
If we want to get a higher amp from a single tp4056 module, for example, what circuit should we add to the module, can we? How is the circuit and its schematic?

 

[Papabravo]

Greetings to the colleagues of the forum
If we want to get a higher amp from a single tp4056 module, for example, what circuit should we add to the module, can we? How is the circuit and its schematic?

I don't think you should be thinking along those lines. This chip was designed for a specific purpose and there is literally zero indication that it can be used outside of those guidelines. At least that is the way I read the datasheet. Do you know something that I don't? There is probably an OTS microcontroller that you could use to build a more capable unit, but charging is not a simple process and there are numerous safety concerns to be aware of. You should check Battery University for a rudimentary look into what you are up against.

Battery University Homepage

Battery University™ is a free educational website offering hands-on battery information.

batteryuniversity.com

Don't shoot yer' eye out kid!
ETA: where the admonition came from

 

[carbonzit]

I'm not disputing anything you wrote, but just want to ask: looking at the datasheet for this chip, wouldn't it be possible to add a pass transistor (BJT or MOSFET) at the chip's BAT terminal to increase the current capacity as the OP asked about?

This all above my pay grade, so pardon me if this is an absurd question ...

Totally agree about Battery University as a great source of info for anything battery-related.

 

[Papabravo]

I'm not disputing anything you wrote, but just want to ask: looking at the datasheet for this chip, wouldn't it be possible to add a pass transistor (BJT or MOSFET) at the chip's BAT terminal to increase the current capacity as the OP asked about?

This all above my pay grade, so pardon me if this is an absurd question ...

Totally agree about Battery University as a great source of info for anything battery-related.

I think you and the TS have made the simplistic assumption that this chip is similar to a voltage regulator. It is -- sorta -- but is much more complicated. How will the PROG pin which sets the constant current into the battery know how to deal with a series pass element that is defeating that operation. So, let's say you slam extra current into the battery, and it heats up, tripping the over temp mechanism and the chip starts limit cycling in an uncontrolled fashion and the battery explodes. Can you say for certain that will NOT happen. OK, then run the experiment, but make sure your medical insurance is paid up. NOT WORTH THE RISK!!
Especially with limited understanding of what is going on. That is why I suggest you develop this idea as an actual project with defined specifications and provisions for the unexpected.

 

[rjenkinsgb]

wouldn't it be possible to add a pass transistor (BJT or MOSFET) at the chip's BAT terminal to increase the current capacity as the OP asked about?

That would pretty much disable both charging and cell protection.

The BAT terminal is the (extremely critical) voltage sense point, that the IC uses to control & limit the charge voltage and protect the cell.

If you add any external components that cause voltage drop (like a transistor base-emitter junction, the charging voltage at the cell will not be read correctly.

In that simple example, the charge would cut off at around 3.6V on the cell (4.2 - 0.6V) so it basically never charges.

The current sensing is also internal to the IC, so the charge current control and limiting would be disabled, if any current passes through an external device.

It would also break the cell undervoltage current limiting, that prevents a failed cell that has developed internal leakage, from being forced to charge. It could cause a faulty cell to burst or catch fire.

 

[Papabravo]

That would pretty much disable both charging and cell protection.

The BAT terminal is the (extremely critical) voltage sense point, that the IC uses to control & limit the charge voltage and protect the cell.

If you add any external components that cause voltage drop (like a transistor base-emitter junction, the charging voltage at the cell will not be read correctly.

In that simple example, the charge would cut off at around 3.6V on the cell (4.2 - 0.6V) so it basically never charges.

The current sensing is also internal to the IC, so the charge current control and limiting would be disabled, if any current passes through an external device.

It would also break the cell undervoltage current limiting, that prevents a failed cell that has developed internal leakage, from being forced to charge. It could cause a faulty cell to burst or catch fire.

Thanks for the expansive explanation.

 

[Tony Stewart]

The only thing you might consider is using 3 units in parallel.

They ought to be set up identically for CC mode, CV mode and cutoff. Then all the safety and heat dissipation can do its job, but you may need a micro fan to prevent cumulative heat rise.

The only thing you should not do is run the batteries under a load while charging, then the CV may never end.

 

[electronium]

I'm not disputing anything you wrote, but just want to ask: looking at the datasheet for this chip, wouldn't it be possible to add a pass transistor (BJT or MOSFET) at the chip's BAT terminal to increase the current capacity as the OP asked about?

This all above my pay grade, so pardon me if this is an absurd question ...

Totally agree about Battery University as a great source of info for anything battery-related.

how with npn or pnp?
p-channel or n-channel? What is its schematic circuit?

 

[rjenkinsgb]

how with npn or pnp?
p-channel or n-channel? What is its schematic circuit?

No. Anything connected between the IC BAT terminal and the cell(s) being charged will stop it charging correctly and/or risk cell failure.

The IC data is here:

https://dlnmh9ip6v2uc.cloudfront.net/datasheets/Prototyping/TP4056.pdf

Also note that is only a charge controller; the cell(s) also need a undervoltage/overvoltage protection module between the cell and the charger or load.

If you need higher charge current, two or more TP4056 modules in parallel should be OK, as Tony suggested.

Or use a totally different charge controller!