I have a pair of Even h3 headphones that had a short to ground on the
positive Voltage supply. The battery has a small circuit board attached
to the terminals, similar battery ct's state "built-in battery
protection circuit module PMC" for overcharging, overdischarging and
short circuit protection. I think the circuit got stressed from being
shorted to ground for too long too many times because the battery has
3.5 V after a short charge (connecting 4.5V directly to the terminals),
but the output voltage from the circuit board is anywhere from 0 to 0.5Vdc.

I'm looking at charging modules on ebay since this is a simple problem
and cheaper than a battery, can anyone recommend a charger module
they've had good luck with?

These looks good to my inexperienced eye, but they're stated to be for
an 18650 battery, I have a small flat battery, I don't know if this
matters.

high current (3A) version
5V USB 1S 3.7V Lipo Lithium Li-ion 18650 Battery Charging Board Charger
Module
https://www.ebay.com/itm/5V-USB-1S-3...d4lT EvZWK95w

lower current version
USB 1S 3.7v 4.2v Lithium Lipo Li-ion 18650 Battery Charging Board
Charger Module
https://www.ebay.com/itm/USB-1S-3-7v...QAAOSwvSxau44y

My battery is similar to this, same 503040 battery but different ct. board.
https://www.ebay.com/itm/503040-3-7v...s/193133417570

TIA
Mike

On 5/20/2020 11:00 PM, Charlie+ wrote:
On Wed, 20 May 2020 00:00:16 -0700, Mike S wrote as
underneath :

I have a pair of Even h3 headphones that had a short to ground on the
positive Voltage supply. The battery has a small circuit board attached
to the terminals, similar battery ct's state "built-in battery
protection circuit module PMC" for overcharging, overdischarging and
short circuit protection. I think the circuit got stressed from being
shorted to ground for too long too many times because the battery has
3.5 V after a short charge (connecting 4.5V directly to the terminals),
but the output voltage from the circuit board is anywhere from 0 to 0.5Vdc.

I'm looking at charging modules on ebay since this is a simple problem
and cheaper than a battery, can anyone recommend a charger module
they've had good luck with?

These looks good to my inexperienced eye, but they're stated to be for
an 18650 battery, I have a small flat battery, I don't know if this
matters.

high current (3A) version
5V USB 1S 3.7V Lipo Lithium Li-ion 18650 Battery Charging Board Charger
Module
https://www.ebay.com/itm/5V-USB-1S-3...d4lT EvZWK95w

lower current version
USB 1S 3.7v 4.2v Lithium Lipo Li-ion 18650 Battery Charging Board
Charger Module
https://www.ebay.com/itm/USB-1S-3-7v...QAAOSwvSxau44y

My battery is similar to this, same 503040 battery but different ct. board.
https://www.ebay.com/itm/503040-3-7v...s/193133417570

TIA
Mike


Poundland cheap £1 Battery bank - they use USB small board to charge and
have BM you can use with 18650 or smaller Li cel - it doesnt matter. C+

Thanks!
https://www.youtube.com/watch?v=XnG86QMxGqw