One Bad Apple…or Battery
You know the old saying about one bad apple causing the whole basket full of them to go bad. The same thing applies to batteries. I am there, now, and so is Mark. Like me, Mark seems intrigued by the Simpliphi lithium batteries, but is also interested in getting a little more life out of what he has. Here’s his note.
Ok, since my 8 Rolls L 16 batteries are 8+ years old, all but one (one cell is 20) are reading good PH, would it be better to get 1 battery new or replace with a Simpliphi? How much do they cost and how many would I need for a 24vDC, 3KW 220 volt a/c system used as a backup on house? It’s the old array and battery bank, we have since added a separate grid intertie array but like both.
We will first consider stretching the life of what you have. I am all for that, but I would NOT buy a new one to mix in with the 8 year olds. Have you given them a good, bubbling equalizing charge? Sometimes that will bring them back.
It may be that you can find a good used one at an industrial battery dealer. Stores like WalMart and Target use L16s in the floor scrubbers and trade them out. Maybe you could pick up a used one, and one that is a better match, for a hundred bucks or so.
Another option would be reconditioning. Here in Pensacola we have an outfit called Battery Guyz that will sell a reconditioned golf car battery for $60 with a one year warranty. Reconditioning includes desulfating, washing them out and refilling with fresh acid. Maybe an outfit like that could refresh your L16.
Now, as far as replacing one of your L16s with a Simpliphi…NO! The L16 is 6v. The Simpliphi is 24 or 48v, depending on the model. You can replace your entire collection of L16s with Simpliphi. Could you keep the one good bank of L16s and run parallel with Simpliphi? I don’t know the battery well enough to answer that question. I have the same question myself as I have two 48v EVs running in parallel to my house banks. It is a possibility I would look into by contacting the company. From what I read about the Battery Mangement System (BMS) I think it is a possibility, but you would probably have to separate the L16s offline when you equalized.
Let’s assume the worst, that we’ll have to swap out them all and start with his L16s’ specs. 8 of them on a 24v system is two strings. Depending on which version he bought, they are good for 390 or 445 amp hours. Let’s just round off to 400 since I hate math. 400ah x 24v x 2sets=19,200. Call it 20kw. Now, you can only safely draw down 10kw, so to replace the entire set of L16s with the Simpliphi 3.8kw units, you’ll need 10/3.8 or 3 of them. Because of all the rounding, they may give a little more drawdown than the 16 Rolls. One Simpliphi, I think, weighs less than an L16, and 3 of them will take up a whole lot less space.
Here’s the kicker. The Simpliphi is rated for 10,000 cycles. That’s more than any other lithium I have seen. 10,000 cycles is 27 years. If you are my age, then that is a “forever” battery. And no maintenance.
You’d have to get with Roberto or Tony for some hard prices, but I would guesstimate that 8 shiny new Rolls L16’s, a premium brand, would set you back around $3000, especially if you throw in postage on those heavy beasts. I think the retail on the Simpliphi is around $3000 each. So you end up paying maybe 3 times as much for 3 batteries as the pile of L16s. Yikes! BUT, now you have more capacity, less maintenance, and may never have to change a battery again. Oh, and bet that if an L16 is $350 today, it will be more 8 years from now!
It’s a bunch of money, I know, but if I am running the numbers right, that sure sounds like a bargain to me. Call Sun Electronics to get up-to-date numbers and an actual quote.
–Neal
Note that earlier I ran the numbers for 16 batteries instead of 8. That gave a completely whacked comparison, but the conclusion remains the same.
Solar Rescue update
Stan called and he was happy.
His old 12v system, pictured above, is really getting tired. It consists of nearly 50 mismatched modules and two windmills in parallel on a single overworked charge controller! His new 24v system is running, but only half-installed and there have been issues.
After our little troubleshooting session the other day, Stan-the-Hermit left the cabin on the creek for a few nights on the beach. He’d returned to the creek to find his batteries were full for a change. Of course, to zing me, he started out like there was some kind of problem.
Best news of all, for the first time ever, he ran his well pump and got all of his tanks charged up so he could bathe. Normally he has to fire up the generator to run the well pump, but it started and the charge held until all four of his tanks were full and the pump shut off. Given that his inverter is of the modified square wave variety, that’s quite a feat, as motors tend to prefer sine wave inverters.
To review what happened, Stan THOUGHT he had 5 of his 10 300+ watt modules connected in parallel to his 60 amp charge controller. Owing to a bad MC4 connector, 3 of them were actually NOT connected. Just as well, because all 5 of them would have exceeded the capacity of the charge controller. We replaced the connector and reworked the arrangement to two series pairs of panels, which reduced the amperage (and loss) on the downlines and gave the controller a little more voltage to work with in the morning and afternoon.
He swears he will finish wiring the rest of the modules and return my big roll of wire. I hope he remembers that if his 60 amp charge controller isn’t big enough for 5 modules, then his new 40 amp controller won’t handle the remaining 6 modules. I’ll be expecting a call next time the sun comes out.
–Neal
Will Has a Question, Part 3 1/2
Here is an interesting battery for Will.
Yes, it HAS been a while since the last post. This time of year just seems to keep me busy.
Last update on Will’s system we essentially concluded he is going to need a huge battery. Batteries should not be a system afterthought. They are probably the most important and expensive part of the system. Do it right and you can minimize having to do it again, unless you can find a “forever” battery.
I know Sun Electronics has several kinds of batteries, because I have been there and seen them. And bought them. The thing is John has all kinds of stuff that never gets shown on the web site until they have a closeout sale. I bet John doesn’t even know what lurks in the back corners. Sometimes it doesn’t hurt to just call them and tell them your situation and maybe they’ll surprise you.
Well, in a conversation with a fellow who got a quote from Tony for a pretty substantial battery, I learned about one that is real interesting. Understand, MY interest because right now I have one bank that is well on its way to ruin and others that are pushing up to 6 years old. I need batteries myself. Golf car batteries are generally considered beginner batteries and the better stuff can cost a lot more. Better can last a lot longer, too, making the expensive stuff cheaper. We’re talking about quality, here.
Well, here’s this lithium battery, the Simpliphi 3.8. It comes in 24 or 48v configuration, 3.8kwh. It is the good kind of lithium, that is they don’t burst into flames. It is much lighter and much smaller than conventional batteries, so if you need a really big (capacity) battery, you don’t have to build a new wing on the house to hold the battery. Apparently the built in battery manager (BMS) let’s you use it like any other battery and, in effect, go to 100% discharge of rated power. The BMS holds the necessary reserve to keep from harming the battery.
So, with a lead acid battery you strive to use less that 50% of capacity to maintain better battery life and the Simpliphi lets you use 100%. That means you have an even smaller pile of batteries in the power room. Throw in a lot more useful cycles (around 10,000) and this battery starts to look economical if you take the long view.
Unit size is 13.5″x14″x8″ and it weighs about 78 lbs. 3 of these weigh about the same as 3 1/2 Trojan T105s and have the usable power equivalent of around 16 of the Trojans! Wow.
It seems there are wall brackets available to fit these batteries, too. Compact, long life, neat installation, no hydrogen or acid fumes and long term economy. What’s not to like?
–Neal