About destroying my LiFePo batteries.
No nightmare here. I am now back in holiday mode. Well, almost. I have gone to the dark side and installed 16 Trojan T-105's. I was unable to get LiFePo on short notice. So sad.
This is what happened:
- Bought 8 Winston 700Ah cells from Ballon in 2013 at $500 each "slightly used"
- installed as 2P4S, no BMS but HVC and LVC with solenoids. Cell Log to see individual voltages.
- first season all was fine.
-
layup 50% charge disconnected
- upon return cell set 2 has dropped in voltage. If I remember right, it was sitting at 2.8 V when I returned after 6 months. Others 3.3V
- next
layup season I kept them connected with the solar charging to 13.2V (lowest I can set the charge controller)
- upon return I had to heavily balance (bleed a lot out of sets 1,3 and4)
- during the season I had to manually balance two or three times.
- next layup connected again with solar controller at 13.2
- I asked,someone to check and set 2 was getting low, so I asked the person to balance as per my instructions. I don't know if that ever happened. I may not. I don't want to dig into it.
Result. Upon return solar was charging. Voltages were:
4.1. 0.7 4.2 4.2
Nicely bulged cells. Surprisingly I was able to assemble a reduced set that tied us over for a multi-day 300Nm trip to
Florida and several days there. Running fridge,
navigation, etc.
One solar set (900W) was still working the other set had one panel ripped out by Matthew. A bolt had unscrewed itself and the
wind lifted the edge and ripped the other 3 bolts. The unscrewed bolt was still siting innocently on the
deck.
By he way. The solar on my
boat is the only thing that truly charges the batteries. The stock alternators never charge the Trojans over 13.2V we had one run of motoring and
motor sailing in light winds crossing the stream of 20 hours.
Today is the first day with running full solar. Max output was 80A for several hours. Max V today 14.2. Will get to 14.6 tomorrow if sunny again. Total solar in 550Ah or 7.3kWh