But at a certain point, a degree of “this is too good to be true” started to set in. For one thing I started wondering if my meters weren’t really being accurate. Very simplified, the meter figures out how much is left in a battery by very accurately measuring its voltage.
This worked perfectly in my old batteries because there is a direct and a linear correlation between voltage and remaining power. These new ones though, put out close to full voltage almost until the very end.
The other thing I was noticing at the same time, my solar charge controller never really left the bulk charge mode. How these chargers usually work, it bulk charges for a while. During this time it is dumping all the energy it can, as fast as it can, into the battery. Then when the battery is about 80% full the charge slows down. This is called the adsorbtion phase. Then when it gets almost full, it changes to a trickle phase as it slowly brings it up and holds it at 100%. Odds are high you are holding something in your hand that works the exact same way. My van should charge just like your phone.
As I say, should. But instead I never saw it switch off bulk charge. For a while I kind of rationalized it. —Because I was also testing the batteries. Hiding out in the shade and keeping a constant eye on all the numbers. Did I tell you I can look at all the cool graphs on my phone? But then I spent a couple of days out in pretty much full sun. The solar panels were putting out some massive numbers because I had done a car wash and they weren’t all covered in Quartzsite dust and road grime. It was constant bulk charge.
Something wasn’t right. I took to hiding out in the shade again and did some more research. I discovered I was using terminology interchangeably when it wasn’t so. What I bought were cells., not batteries. Strap a number of cells together and add something called a BMS (Battery Management System) and then you have a battery. This was a distinction I had not understood. When I was reading the product descriptions on the solar charge controller it was using some of the same battery management type terms so I thought it handled it and I was set.
I was not set.
It was right about this point in time something bad happened. I spent a day parked in what turned out to be a super shady spot, but I had been really busy at work. I didn’t want to take the time to pull the dish in, find a sunnier spot and get logged in again. And my meters said 93%! Next day was not a workday but it was raining. I moved to what would have been a good sunny spot and I did get a tiny amount of solar but not much due to the hard rain. Honestly, I was bored AF. Even with my poncho, hard rain kinda sucks, and I think I was having a foot problem. I didn’t want to walk in the rain. I put the dish out and watched TikTok videos almost all day. I didn’t quit until I looked up and noticed my battery level meter said 59%.
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| Rebuilding the van electrical system, parking lot edition. |
I felt like I had looked at it not that long before and it was in the low 80s. I called it a TikTok night, pulled the dish in and moved into my night time parking spot. The dish does draw a lot of power and so unplugging it the batteries bounced back. Levels went back into the 60s. But it was only about six in the evening. Too early to go to bed. It was warm enough the furnace wasn’t running so I just ran the lights. I pulled out my Italian version of Harry Potter, The Prisoner of Azkaban, and tried to learn some new words. A few hours later and the battery bounce looked short lived. At this point my two battery level meters diverged. My old one was reading 51% but the new fangled one I had just installed was reading 35%.
What I *should* have done at that point was gotten dressed, got my rain poncho on, gone outside around to the back of the van and pulled the main service disconnect. Disconnecting the batteries completely. What I did instead is, attempt to rationalize *not* getting wet by saying with the lights off, I consume very little electricity. This was a very unfortunate mistake. By morning the batteries were totally flat. 0%. I moved into the early morning sun but instead of seeing charge numbers I was seeing error messages.
Of course my luck wouldn’t stop there. It was a cold front pushing in and bringing the clear skies. The forecast was for high forties by nightfall and lower the next day. The van was dark. I still had to work, I drove to a coffee shop and logged in from there. But spent a lot of time fretting and stewing over exactly what my plan was going to be if I didn’t get this working. Over lunch break, I have no idea what I did over several iterations of disconnecting and rebooting but all of the sudden it started to charge. Happy ending for the day, but it was a bad deal. Drawing a battery all the way down to zero always causes some battery damage. I don’t know how much.
After that the weather was pretty cooperative. Things were back to 100% by noon the next day. Then after that I tried to do some pretty close management of my levels and how much I was in the sun. In the meantime I posted on a couple of forums.
—Let me take a quick side trip here to tell you about something cool. My solar charge controller has bluetooth and I can connect to it with my phone. One of the tabs on the app I have to run to do this is a community support forum. People who own the same equipment helping each other! Every once in a while technology gets something right.
Anyway, I posted describing my situation and was immediately taught the different between cells and batteries and told I absolutely needed to have a BMS installed. I asked for recommendations and was told to buy an Overkill Solar brand BMS and wire it into my system. I was able to order one on Amazon and have it delivered to an dropbox in New Orleans close to where I sometimes park. A pretty cool story too but I will close this out and save that one for next time.
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