off.the.grid
New Member
- Joined
- Dec 26, 2021
- Messages
- 124
Yes sure thing, I got caught out that day as I thought there was plenty of charge.First off is to gain an understanding of what a battery is. Batteries are a chemical device and not a can of gasoline. A good write up is at: https://climatebiz.com/battery-capacity/
All the well meaning advice on proper charging techniques does not change the basics. Voltage as a indication of capacity is a real loose measurement. Frankly most inverter setups have a ridiculously low voltage cutoff as standard. By the time they cutoff you have already passed where it is good for the batteries chemistry to be at. As a illustration about voltage and capacity is solar panel Voc rating. You can see a high voltage on you panels in dim daylight with no load. However try loading them and the voltage drops like a rock if they are not in full sunlight. Your batteries can show normal voltage also without load. However they lack the chemistry inside to deliver anything.
Rather than waste too much time in the weeds in micromanaging your charging you probably want to look at your loading and solar supply. Suffice to say, if you can avoid putting much use on a battery you are better off.
If 10.8V is too low for 50% I might raise it to 11 volts to be safe. But I doubt I will be draining these batteries much in a typical day.