Charging Lithium

 A year ago, I made the leap to lithium (LiFePO4). My lead AGM gave up the ghost, the result of a failed solar panel allowing it to go flat for too long. It was also long in the tooth. I wrenched my shoulder maneuvering it out of its hold, which was horribly located, so the decision was significantly based on its being half the weight. 

 I'd read up on lithium. I picked one that had been vetted by a battery expert I trust. The BMS (battery management system) would cut off charging below freezing, which can be an issue for me. We've all been told that charging below freezing is bad, resulting in lithium plating. But ...

1. 32F has no particular significance to a system that does not contain water. It sounds like just a number that is easy to remember.
2. I have read in several places that, in fact, it is a soft number, and that what matters is tapering off the charge rate at low temperatures. That at some low rate, charging in the cold is non-damaging. 

One source said 0.05C (5% of battery capacity) may be considered safe. My panel can only charge 0.025C on the best of days, and typically more like 0.010C in the winter, when this would matter. 

 C= charging rate/capacity. Many of the studies were done at C=1 to 3, meaning that a battery could be fully recharged in 20-60 minutes. That's FAST for solar systems. I doubt many sailors can recharge the bank in less than 5 hours, and most, more like 10-20 hours (C=0.1 to 0.05).

 

 

It's never clear how far you can extrapolate data without more  testing, but it seems clear from the above graph that at very low charging rates, the effect of temperature on plating (low temperatures) and side reactions (high temperatures) are much less than at common charging rates. While it is convenient to repower you EV, cell phone, or device in an hour or less (C=1 to 3), that has no application to sailors charging from solar (C=0.1 to 0.05 or less). I'm guessing that curve is pretty flat, and that even if it is not, the cycles at C=0.025 at 32 F are probably better than C=1 at 20C. 

 

How about those apples? Nothing for sailors to worry about. 

 

Someone asked about copper fouling

They seemed to think that copper oxide or copper oxychloride were somehow different, because. obviously, bronze props foul. 

These pipes were in the water for a year. The only one with no hard grow (zero) is the plain pipe with no anode. 

Where did they think the idea of copper sheathing came from? 

 I think they slept through chemistry class. 

 

Does it feel like current events in the middle east were PLANNED to perminantly close the Straights of Homuz ...

 ... to the sole benefit of US Big Oil? I think so. This seems ... obvious.

We have radicalized countless people in the Gaza and Iran. How could we not have? With the rise of drone-based munitions, it won't take much to harass most anything, forever, including the Straights. You don't have to close them air tight to convince shippers to make other plans and to increase shipping costs. That is all that is needed.

Drawing out the war in the Ukraine serves the same purpose; US oil and LNG exports to Europe have surged. The longer it lasts, the hotter it gets, the longer it will take for Europe and Russia to normalize relations.

It seems we have intentionally created a new "warm" war, that won't end, at the cost of many lives, at huge cost to the taxpayer,  to the sole benefit of Big Oil.

 ----

 I can see this. It seems ... Obvious. The only alternative is that Donald Trumps is massively stupid. Possible. But I think corrupt and self-serving is far more plausible and likely.

 Can we afford such intentional mismanagement of world events? Forget your politics. By the time all is said and done, your PERSONAL share is going to be a new car. Bullshit.

A Little Known Cameo from the Sixth Sence

 Sorry. I couldn't help myself.

Eagle at the Masthead

Bald eagles were very nearly extinct when I was a boy. The first one I saw in wild was under a bridge in my 20s. Now they have become so common as to become destructive pests in the marina. 

  

 

This bird was less damaging (1" = 1' scale model of my F-24, made from rebar and 3/16" wire):

 

 

The carnage: I'm not anti-eagle, but For the last two years I've given up on wind instruments aloft, after replacing two vanes, only to have them destroyed. I've been using shroud ribbons and bow vanes, which work very well.