I have a 18 V 1.5 A battery. But when I test the output it shows 21 V. Could I use this on a 19 V 1.5 A router as backup (UPS) Tx. Input on the device shows 19.5 V if I test it.
Asked
Active
Viewed 47 times
1
-
2Welcome! Is that 1.5 _Ah_ battery? – winny Feb 08 '23 at 13:01
-
Does this answer your question? [Choosing power supply, how to get the voltage and current ratings?](https://electronics.stackexchange.com/questions/34745/choosing-power-supply-how-to-get-the-voltage-and-current-ratings) – winny Feb 08 '23 at 13:02
-
Yes it is a 1.5A battery. – Andre Prinsloo Feb 08 '23 at 17:36
-
1Let me rephrase. Does your battery have 1.5 ampere (A) max current or does it have 1.5 ampere-hour (Ah) capacity? – winny Feb 08 '23 at 17:44
-
O sorry. It has 1.5Ah – Andre Prinsloo Feb 09 '23 at 18:15
-
1I have tried the battery on the device and it works like a charm. Lasted for a bit more than four hours. Thanks for your help. – Andre Prinsloo Feb 09 '23 at 18:17
1 Answers
0
The voltage of a battery ranges about +/- 10%1 around the so-called nominal value (the value that it has written on), depending on the load level. Particularly if you have a fully charged battery and you're measuring it using a voltage meter, which doesn't impose any load on the battery, it will show significantly higher than the nominal value.
Whether you can use this battery for your backup will depend on what electronics you use to control its charge/discharge current. You typically can't replace a voltage-regulated PSU with a battery, just because the voltage of a battery is not constant. You need some kind of charge controller (or a real UPS to attach the battery to).
1The exact voltage that defines a full or empty battery depends on the chemistry and other factors of the battery used.
