I have a heated jacket that is powered by a li-polymer battery. The battery has a small board in it, probably to prevent over charging and give display readings to a built in LED.
The battery is 7.4v /4400mAh
The mains charger I am using outputs 9v dc 1A. I have put a volt meter on the charger output and it reads 9v. I believe I am using the correct charger but it is hard to be certain as I have lots of chargers.
In order to trace why the jacket no longer heats up I put an ohm meter on the terminal going into the jacket and the reading indicated that there was no brake in the heating circuit ie the resistance reading went down to almost zero. I assume this means there is continuity. .
I have tried another similar battery and that one is not heating the jacket.
The batteries have leds that show the amount of the charge on a scale of 1- 9, and micro switches that enable the heat output to be varied ie 1-4. When the battery is connected to the jacket the heat output values should be alterable. I can not change them from the lowest charge value of 1 and then that does not remain for long as the LED turns off. This usually means it is not properly connected and no power is coming from the battery. Put the battery back on the charger and the charge scale changes to 7 on one and 9 on the other.
I have another charger that is specifically stated to be for Li-ion. Its output is 8.4v dc 1A. I do not know if I can use that charger, as an alternative, on the jacket battery, as a test to eliminate the charger as the cause.
I complained to the jacket company about one of the batteries assuming the battery had failed and was sent a replacement which also does not heat the jacket.
Some time ago I found that there was a break in the jacket cable and replaced the jack socket by soldering in a replacement cable and socket. I assume that the polarity of the cable will make no difference to a heating circuit as the original cable showed no distinction between the covering of the two wires.
I do not know what else to check and hope you can give me some guidance. One question is about the chargers. As their output voltages do not exactly match the battery output voltages will that have any impact on the chargeability of the batteries?
Robin
The battery is 7.4v /4400mAh
The mains charger I am using outputs 9v dc 1A. I have put a volt meter on the charger output and it reads 9v. I believe I am using the correct charger but it is hard to be certain as I have lots of chargers.
In order to trace why the jacket no longer heats up I put an ohm meter on the terminal going into the jacket and the reading indicated that there was no brake in the heating circuit ie the resistance reading went down to almost zero. I assume this means there is continuity. .
I have tried another similar battery and that one is not heating the jacket.
The batteries have leds that show the amount of the charge on a scale of 1- 9, and micro switches that enable the heat output to be varied ie 1-4. When the battery is connected to the jacket the heat output values should be alterable. I can not change them from the lowest charge value of 1 and then that does not remain for long as the LED turns off. This usually means it is not properly connected and no power is coming from the battery. Put the battery back on the charger and the charge scale changes to 7 on one and 9 on the other.
I have another charger that is specifically stated to be for Li-ion. Its output is 8.4v dc 1A. I do not know if I can use that charger, as an alternative, on the jacket battery, as a test to eliminate the charger as the cause.
I complained to the jacket company about one of the batteries assuming the battery had failed and was sent a replacement which also does not heat the jacket.
Some time ago I found that there was a break in the jacket cable and replaced the jack socket by soldering in a replacement cable and socket. I assume that the polarity of the cable will make no difference to a heating circuit as the original cable showed no distinction between the covering of the two wires.
I do not know what else to check and hope you can give me some guidance. One question is about the chargers. As their output voltages do not exactly match the battery output voltages will that have any impact on the chargeability of the batteries?
Robin
