Suitable power supply for my li-ion charging cradle

[jgarnold]

The power supply for my li-ion charging cradle has failed and the manufacturer cannot supply a replacement (factory gone out of business).

It has a rated output of 21 volts DC 1.4A and plugs into a cradle which attaches to a li-ion battery rated at 18 volts for charging.

The charging cradle has a circuit board inside and so I assume it controls the charging including switching off when the battery is fully charged. The socket on the charging cradle has a typical DC type socket which the power supply plugs into and 4 pins which engage with the li-ion battery.

I can purchase a generic switch mode power supply which has selectable voltages but none are 21 volt. The closest are 20 volts and 24 volts. Would the 20 volt output be too low? Would the 24 volt output be too high?

 

[Harald Kapp]

Would the 20 volt output be too low? Would the 24 volt output be too high?

That depends on the construction of the charger board. Play it safe and use an adjustable power supply set to 21 V.

 

[jgarnold]

Thanks for your quick response.
I did not know that variable power supplies existed and now after searched Ebay have found one of a suitable current available even cheaper than the one which has selectable voltage (eg 18v, 20, 24v).
Thanks again