[SOLVED]CubeCell charging battery current (mA)

Hi.
How to change increase the charging current battery.
On schematic diagram is only 80 mA, but the resistor which is responsible for it is not marked.

image

Replace this resistance can have a higher charging current. It’s 10K by default.

10K ~ 100mA
5K ~ 200mA
2K ~ 500mA

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Is there a downside to changing this to 2K? If not, then why is it 10K by default?

I’m guessing that this resistor sets the MPP for the solar panel and changing it may result in lower performance when using a solar panel for charging.

I am not connecting a solar panel so I guess there is no downside thanks

hello,
I have the same issue because I want to use a big 3300mA battery and 80mA will take forever to charge from solar panel.

could you please confirm the size of the SMD footprint for this resistor?

is this a 0402 or a 0603 ?

thanks

The charging IC is TP4054, it is a linear battery charging IC with 800mA absolute maximum charging current limit. 500mA, by adding an external resistor between 5V and Vin.
I recommend running it below 450mA.

The resistor one my AB01 is 10K 0402, you should check your board.

hi ksckung,

all my AB01 board have a charging current of ~100mA so I assume the resistor is 10k.

450mA is fine, from the datasheet of TP4054 I see that we need to use a resistor of about 1.8k on the PROG pin.

could you confirm the size of the smd resistor? is it a 0402 or 0603?

so that I can buy the replacement part

thanks

hi,

It is 0402 package.

?? I said it is 0402.

The resistor one my AB01 is 10K 0402, you should check your board.

yup, sorry ksckung, you are right, it was written in your reply already.

thanks everyone, crystal clear.

FIY: for all the people interested in using a higher battery with higher charge current.

I did few tests with 1.5K, 1.8K, 2.2K with a 18650 3300mAh battery.

even using 2.2K at ~300mA charging current the TP4054 becomes too hot. If you have a conformal layer like me it will ruin the coating.

I’ll do some more tests with 4.K (~150mA charging current) and report back

hello everyone.

not sure if this is still useful info or not … but after many tests I believe 5.6Kohm is the minimum we can go without stressing too much the temperature of the lipo charger.

with 5.6k I get ~186 mA charging current vs the usual 90mA … the charger does get quite warm … borderline hot … but seems ok.

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Can you mark the resistor for setting charge current on CubeCell GPS-6502 board?

hi,

i don’t konw your hardware version. Please refer to the picture for approximate location:

Hi guys, (electronic noob here), I made my custom PCB (with AM02 module). I share my 5V/charging side.


-I deleted the led status connected to the TP4054.
-I use a XC6206P332MR instead of the recommended CE6260. (disponibility of LCSC components).
I also use a 6V solar panel and a 18650 battery.

By the way, here is the reference design I used

I’m looking for increase the charging too.
-What is the number of the resistor you are talking about on the reference design ? R15 ?
-With a 5.6k resistor, there is a risk of using a small LiPo battery (350mAh) instead of a 18650 ?

A1) R15 in the reference design, R10 in your schematic.
A2) you need to check your battery datasheet. A normal Li-po battery charging current is 0.2C, which means 0.2xcapacity=0.2x0.35=0.07A
i.e.:
Rprog= 5.6K , charging current=173mA
173/350=0.49C will damage the cell

image

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