How To Tell How Full Your Solar Batteries Are
I found this useful deep-cycle battery FAQ that included a rough voltage level chart which helps you determine how full your deep-cycle battery is:
| State of Charge | 12 Volt battery | Volts per Cell |
|---|---|---|
| 100% | 12.7 | 2.12 |
| 90% | 12.5 | 2.08 |
| 80% | 12.42 | 2.07 |
| 70% | 12.32 | 2.05 |
| 60% | 12.20 | 2.03 |
| 50% | 12.06 | 2.01 |
| 40% | 11.9 | 1.98 |
| 30% | 11.75 | 1.96 |
| 20% | 11.58 | 1.93 |
| 10% | 11.31 | 1.89 |
| 0 | 10.5 | 1.75 |
While I haven't blogged about it, I have a small solar panel setup on my patio which provides enough power to run a few lights in my living room each night for a few hours. This information lets me know how charged the battery system is. Right now my battery is at 12.75 volts.