Voltage set point alarm

I have an electric assisted surrey bike. The battery when charged properly reaches 54-58vdc. It’s a lithium battery. The charger has indicator led lights to show when fully charged. The manufacturer strongly recommends that the charger be removed when the battery reaches a full charge but it takes 6-8 hours so I could be off doing anything. I basically want an audible alarm when the battery reaches a set point of 54-58 volt DC. I’m a beginning electronics hobbyist and can readily build it but just starting to learn design and help would be awesome. Thank you.

by BernieX
September 05, 2019

"The charger has indicator led lights to show when fully charged". You can use this light voltage to turn on your alarm.

by wangwg88
September 05, 2019

Wow. That is so obvious! I totally didn’t consider that. Your idea is great and I appreciate it so much. I’ll crack open the charger and do just that. Thank you for taking time to read and post a response. This is an awesome site, so glad I found it.

by BernieX
September 05, 2019
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