Battery Capacity Monitor with Audio Alarm

 

Lead Acid AGM batteries still remain the lowest cost option for off-grid power. They are low cost, robust, and can work over a wider temperature range than Lithium batteries.

 

They can last many years as long as they are not discharged below 50% capacity too often. This Battery Monitor with audio alarm starts beeping as the battery capacity drops down to less than 50% and then with increasing persistence as the battery capacity drops down even further - it is hard to ignore. The money spent on this alarm can be easily recovered by extending the life of the battery.