March 11, 2017 § Leave a comment
We were going to baby the old batteries along until we just had to replace them but we ran across two batteries that had just been delivered. With the date stickers indicating the current month, we were pretty sure that the batteries were fresh so we pulled the trigger and bought them.
The first change we observed was the internal resistance of the batteries. The old batteries would drop about 0.23 volts when the television and a light turned on. The new batteries drop about 0.05 volts.
Most advice is to break new batteries in slowly by not discharging too deeply. We’re probably doing well with that since we have yet to discharge beyond 12.53 volts which is equivalent to about 91 or 92 percent state of charge.
Our battery monitor is showing that we are drawing as much as 24 amp hours to arrive at that state of charge which is much more than the 8% or so reduction in charge which would be something like 15 amp hours. We think this is because the sun is setting later and there is some fading as well as surface charge involved. All charging of the new batteries so far has been with the solar panels. The extra amp hours do vary some from day to day so it’s hard to pinpoint any cause and effect for this phenomenon. The results are welcome though.
The added capacity of the new batteries will come in handy when we hit the road later this month.