# Pico Lipo not charging
**URL:** https://forums.pimoroni.com/t/pico-lipo-not-charging/23267
**Category:** Support
**Created:** [November 11, 2023, 7:11pm UTC](https://forums.pimoroni.com/t/pico-lipo-not-charging/23267 "2023-11-11T19:11:22Z")
**Posts on this page:** 10
**Page:** 1
### Author:  [@renato0307](https://forums.pimoroni.com/u/renato0307)
#### Post date: [November 11, 2023, 7:11pm UTC](https://forums.pimoroni.com/t/pico-lipo-not-charging/23267/1 "2023-11-11T19:11:22Z")
Hi,
Just got a Pimonori Pico Lipo with a [battery](https://mauser.pt/catalog/product_info.php?products_id=035-4577).
Flashed a simple blinking example and works on battery.
But the charging light is not on when connected with USB.
Any idea?
Thanks,
Renato Torres
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### Author:  [@renato0307](https://forums.pimoroni.com/u/renato0307)
#### Post date: [November 11, 2023, 7:19pm UTC](https://forums.pimoroni.com/t/pico-lipo-not-charging/23267/2 "2023-11-11T19:19:05Z")
On USB:
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### Author:  [@renato0307](https://forums.pimoroni.com/u/renato0307)
#### Post date: [November 11, 2023, 7:20pm UTC](https://forums.pimoroni.com/t/pico-lipo-not-charging/23267/3 "2023-11-11T19:20:54Z")
On battery:
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### Author:  [@Shoe](https://forums.pimoroni.com/u/Shoe)
#### Post date: [November 11, 2023, 10:05pm UTC](https://forums.pimoroni.com/t/pico-lipo-not-charging/23267/4 "2023-11-11T22:05:54Z")
At a guess, your battery is wired the wrong way around. Look at the +/- symbols on the board: your red (positive) wire is connected to the negative end of the charging socket.
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### Author:  [@renato0307](https://forums.pimoroni.com/u/renato0307)
#### Post date: [November 12, 2023, 9:02am UTC](https://forums.pimoroni.com/t/pico-lipo-not-charging/23267/5 "2023-11-12T09:02:09Z")
It’s connected correctly, it’s just the PH connector that has the colors the other way around.
The Pico works connected to the battery. It just doesn’t charge.
The first time I connected I didn’t realize the colors where switched, maybe I burned something up on the charging circuit.
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### Author:  [@Shoe](https://forums.pimoroni.com/u/Shoe)
#### Post date: [November 12, 2023, 9:58am UTC](https://forums.pimoroni.com/t/pico-lipo-not-charging/23267/6 "2023-11-12T09:58:28Z")
From what I gather there’s no law around which way battery connectors need to be wired up, but they need to match the socket you’re pluging into.
The datasheet for the battery charging IC says it has reverse polarity protection, so it should be OK? I doubt it’ll charge unless you fix the polarity though. I have absolutely no idea how the board is running with the wrong polarity! The product page doesn’t mention rectifiers at all.
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### Author:  [@alphanumeric](https://forums.pimoroni.com/u/alphanumeric)
#### Post date: [November 12, 2023, 1:08pm UTC](https://forums.pimoroni.com/t/pico-lipo-not-charging/23267/7 "2023-11-12T13:08:39Z")
@Shoe If you look close I think you will find he has Battery Red connected to Plug Black and vise versa where the wires were cut.
My best guess is the LED is backwards on the board. You should be able to run a battery example to see if its charging. I thought I had one saved for the Pico Lipo but don’t see it now.
Found this link on the shop page.
[pimoroni-pico/micropython/examples/pimoroni\_pico\_lipo at main · pimoroni/pimoroni-pico (github.com)](https://github.com/pimoroni/pimoroni-pico/tree/main/micropython/examples/pimoroni_pico_lipo)
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### Author:  [@renato0307](https://forums.pimoroni.com/u/renato0307)
#### Post date: [November 12, 2023, 1:55pm UTC](https://forums.pimoroni.com/t/pico-lipo-not-charging/23267/8 "2023-11-12T13:55:32Z")
Yes you are right @alphanumeric.
In the first time I connected everything I did red-red / black-black without noticing the polarity of the plug.
The Pico was not booting and got a bit hot.
Only after I noticed and changed the connections.
The Pico started to boot but the battery was not charging.
I might have damaged the charging circuit.
I’ll try the example @alphanumeric, thanks.
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### Author:  [@renato0307](https://forums.pimoroni.com/u/renato0307)
#### Post date: [November 12, 2023, 2:07pm UTC](https://forums.pimoroni.com/t/pico-lipo-not-charging/23267/9 "2023-11-12T14:07:24Z")
Ran the following script, for some time without USB connect to let it drain for a bit.
it went from 3.93V to 3.88V:
Now going to run the script with USB connected and see if it charges (even if the led is off).
```auto
from machine import ADC, Pin
import time
import os
soil = ADC(Pin(26))
readDelay=0.5
min_moisture=41498
max_moisture=65535
vsys = ADC(29) # reads the system input voltage
charging = Pin(24, Pin.IN) # reading GP24 tells us whether or not USB power is connected
conversion_factor = 3 * 3.3 / 65535
full_battery = 3.9 # reference voltages for a full/empty battery, in volts
empty_battery = 3.0 # the values could vary by battery size/manufacturer so you might need to adjust them
writeMode = True
if writeMode:
i = 0
try:
os.remove("log.txt")
except:
pass
while True:
i += 1
if i > 300:
i = 1
try:
os.remove("log.txt")
except:
pass
with open("log.txt","a") as f:
voltage = vsys.read_u16() * conversion_factor
percentage = 100 * ((voltage - empty_battery) / (full_battery - empty_battery))
if percentage > 100:
percentage = 100
moisture = (max_moisture-soil.read_u16())*100/(max_moisture-min_moisture)
print(i, charging.value(), '{:.2f}'.format(voltage) + "v", '{:.0f}%'.format(percentage), '{:.0f}%'.format(moisture))
n = f.write('{}'.format(i) + ",")
n = f.write('{}'.format(charging.value()) + ",")
n = f.write('{:.2f}'.format(voltage) + "v,")
n = f.write('{:.0f}%'.format(percentage) + ",")
n = f.write('{:.0f}%'.format(moisture))
n = f.write("\n")
time.sleep(readDelay)
else:
with open("log.txt","a") as f:
s = f.read()
lines = s.split('\n')
for l in lines:
print(l)
```
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### Author:  [@alphanumeric](https://forums.pimoroni.com/u/alphanumeric)
#### Post date: [November 12, 2023, 6:28pm UTC](https://forums.pimoroni.com/t/pico-lipo-not-charging/23267/10 "2023-11-12T18:28:19Z")
> [@renato0307](#):
>
> In the first time I connected everything I did red-red / black-black without noticing the polarity of the plug.
> [@renato0307](#):
>
> I might have damaged the charging circuit.
I’d say you damaged something, as it got hot etc.