Battery ?'s

shokman

Help! So it would seem that I have lost my 4 L16 6v (S-550 I believe 450ish Ahr) batteries after 5 years. It all started with me not being at my lake property for several months late last summer and I boiled them below the plates. Now I need to replace bank and have concerns as to what to replace with. My dilemma is as follows. They are in a root cellar under house and will require some creative rigging to get them out. I also want to replace with something that does not require maintenance  as I may not be there for long periods of time. I like the idea of lithium as I can manage the weight but of course afraid of the cost. The other thought is golf cart size that I can manhandle,however would have to be AGM or somehting that does not need water maintenance ? I would also not want to have to replace exsisting equipment which is Classic 150 and old Trace 12v inverter. I have 1000w of solar but do plan on up grade when I get a new roof on the house which may not be until spring. What say you?
Marc

JRHill

If you have those 4ea L-16 FLA batteries under your house you are not worried about fire/fumes, are you? People wring hands over burning lithium batteries so you are not worrying much about that issue.

Issue 1 is that big bank with 1000 watts of solar for charging. Not good;
Issue 2 is 12vdc. Sorry, not good;
Issue 3 is the charging and discharging voltage limits of a lithium battery and your old equipment is, not good;
Issue 4 is the temperature limits of lithium batteries if they get too cold is not good. But who knows where you are?

You don't have any cheap way out as it looks but there are too many unknowns to say for sure.

littleharbor2

I don't see any problem with the Classic 150 as long as it still works.
Diy lithium is actually cheaper than lead acid depending on the price of golf cart batteries in your area.

SteveK

Real root cellars are typically ~40F. Many run warmer like ~50F. Would be nice to know how cold your root cellar gets. Keep in mind the Lithium (LFP) are limited to above freezing charging and it is highly advised above 40F for ultimate longevity. However, LFP can be discharged below freezing and will self heat somewhat once they are discharging so that can be a moot point while you are visiting the camp.

For the low(ish) panel wattage of 1kW LFP is fine. No need to bring LFP's to full charge regularly like FLA. LFP can reside nicely at mid SOC for years. No need to equalize either.

For the extended unattended operation like you had last summer LFP would be better than FLA. If you can disconnect the batteries before you leave that works best for FLA and I'd say the LFP's too. The BMS in the LFP's will shut down saving your batteries. LFP's are much lower maintenance.

No problem with the Midnite Classic though it would be nice if they updated a couple things on it for LFP. No experience with the Trace.

I'd do LFP. I regularly use LFP in below freezing temps. Doesn't take much energy to self heat them if need be. Insulation is your friend.

Only consider LFP's with low temp shutdown built-in. Providing that after the fact can become convoluted.

shokman

Okay sorry for the time gap, my root cellar goes from a low of 5c in winter and a high of 21c on summer so not worried about temp. I have heard all about the downside to 12v system but the only take away I got was the line loss at low voltage so I do have very large cable from panels to house and 2x00 cables from batts to inverter. I have ofter thought about upgrading the old Trace tank of an inverter but all I hear about all the new ones around me is inverter problems and they are name brand. I was also told by someone in the biz to not expect mush more that 10 trouble free years ??? the only fear I ever had with FLA was fire which I was told to vent them properly (which I have not done). So going to LFP was a concern but I'm assuming that problem has been dealt with with the built-in BMS ? again I know nothing about LFP

SteveK

Although the BMS is a great thing that allows some cell level control and reporting they can also become a thorn and a weak point of failure in your design. This is one of the reasons why you will hear so many folks praise the higher quality/cost LFP battery solutions like those that are offered for sale here on NAZ's website and other competent places. Places that choose what they offer carefully for good reason because they care about building safe long lasting systems and relationships.

One common theme you should listen to is this. The BMS should always be regarded as a safety and reporting device and should not be implemented in such a way in which it breaks your daily charge/discharge current directly. Your charge controller and inverter/charger should be capable of reliably performing those operations independently from the BMS. As a matter of fact, the most reliable BMS's do not "gate" the charge/discharge current at all. In the error event they simply send control signals to other devices like the charge controller, inverter/charger and/or contactors to actually throttle the current on/of. Sometimes you can't get away from the built-in BMS with built-in current control and that can be OK as long as you buy a quality BMS or battery/BMS solution and understand the risks.

Of course the BMS performs other functions like cell balancing, cycle counting, SOC and comms. One thing it does not provide directly is fire suppression. Oh, and be aware that the BMS (with current gating) is the component that is most likely to introduce actual flame in to the equation. This is why some manufacturers install multiple fire arrestors within the battery pack/module itself. This because the actual cells won't flame up unless physically punctured but the BMS can flame up and cause a chain reaction within the battery module.

With regard to your root cellar. From my experience they are pretty humid and condensing. Is yours? Choosing components that are suited to the wet environment is a thing. Galvanic corrosion and plating at the board level should be considered. Not sure if your Trace and Midnite reside down there too but with LFP your might be bringing electronic components in to that environment so a sealed or conformal coated solution would be required in a condensing high humidity environment. Not a biggie for FLA.

Hope this helps.

shokman

Thanks for the technical brief that is exactly what I'm after. No my hole does not have a moisture problem. Cabin is in the Thompson valley in British Columbia which is the only Semi-Arid climate in Canada and hole not a proper "root cellar" It is 5 x 9 ish hole under house that that is block lined to ground level with wood 2ft framed wall to meet house floor. Batteries are in cellar, inverter is under house 3ft away accessed through small panel. Charge controller is directly above inside house. I have a thermometer under house and have never seen below freezing temps. We are on north side of large lake (Kamloops Lake) facing due south. We get small amounts of snow in winter and usually melts as soon as sun comes out. When it is -20C (-5F) people around here are pretty cold :>). If I was afraid of battery explosion I could build an enclosure outside??
 So I have looked on site at batts LFP and see Surrette has them, they are probably accessible in my town.  Wondering if I would need additional components to operate savely ??

shokman

My other ? is if I had 900ish amp hours with my 4 L16's and seemed to be enough, what would I need to replace understanding that LFP would allow use of more than 50% of capacity and what wattage of panel would be required? I did not mention that I also have 2 30amp Iota chargers that I can parallel but only use them in winter when light hous are short or we go through a period of inversions which is typical in late dec through January. We have been known to spend winters out there. If house is heated (wood) no need to winterize water system. 

SteveK

I'd feel real comfortable with a bank of Rolls/Surrette's under my bed. They don't seem to have the fire arrestors but most don't. They have built-in heaters, a nice plus for your outdoor enclosure. One thing is for certain, the quality is there and I'm sure the price reflects that. Shopping local in such a rural area is also priceless for support.

You will need to decide if you will want to maximize the lifespan of the batteries or push 'em harder to save some money. 80% DOD is listed at 6000 cycles. 100% DOD is listed at 3000 cycles. Assuming you are going for their 12V 100ah versions you will get 880ah useable from 11 batteries with DOD of 80% or 900aH from 9 batteries with DOD of 100%. You have a dilemma with the 100aH version though. They can only strung together in max series string of 4S and max parallel string of 4P or 4S4P. You will need to configure your battery bank with other battery models within the Surrette line-up. I did not look at all their models but the same math applies as I listed above. Your dealer should be able to find the model that works best with the system components you already have.

You have the Classic that can be set to 12v, 24V, 48V battery banks. Not sure of your panel count or VOC ratings and can they get you to 24V or 48V if need be. This would help in configuring a battery bank.

I am unsure of the Trace. Is it capable. You should already have cabling and fusing that should work. I like the outdoor enclosure idea. I would probably nestle them in the root cellar myself but I also gamble too much sometimes so there's that.

BB.

LiFePO4 chemistry is probably the "safest" of Lithium Ion battery chemistry.

However, anything with plastic (and lithium, etc.) can burn given the right conditions (say a short circuit lights off a cable tray, burning plastic drips down on the battery bank and lights the plastic cases/lithium inside). I am just very worried that water on a lithium battery fire will produce some very toxic Hydrofluoric acid--As well as a fire that water itself cannot putout (unless you fill the cellar with water).

Lead acid battery fires are still not "fun", but Lithium fires can end up being a toxic nightmare (as in very toxic to humans. HF Acid--read about it). While a good design should never get into a total fire loss--I would still prefer a separate building/area from the home to both protect people living in the home, and have an area that I could scrape down to bare earth to clean up (i.e., a cheap battery shed/cellar vs my entire home).

Also--Fire Insurance. Make sure that your installation meets code and your insurance company requirements (if you carry fire insurance). We have had a few comments here that Insurance Companies have been known to look into the details of an off grid installation to decide if they will cover damage or not).

-Bill

SteveK

Yes, to Bill's point, this makes the fire arresters more important. Here in my jurisdiction ONLY lithium (all chemistries lumped together senselessly) are allowed to be installed inside the home. No FLA. Basement install only.

No water on lithium fires, period. The Fire Department is to know this.

Each of my home modules has two built-in fire arrestors. The cells are enclosed in steel and those are also enclosed in metal racks. My rv's both have lithiums. One has LFP only and one has LFP and NCA both.

JRHill

I'm not worried about the SimpliPhi's in the crawl space. The question is if I can get ~50 lbs of various reloading powders and a 50 cal ammo box full of primers out of the house fast enough. Then there's the built ammo. And, oh yeah, the black powder stuff. If I can't then its how far away from the house can we get? Hopefully the propane tank won't go or the oxy-ace tanks in the shop or the diesel and gas in storage. 

  

SteveK

JRHill said:

 And, oh yeah, the black powder stuff. If I can't then its how far away from the house can we get?

  

I would say this is a great question worthy of testing. Let's pile on some kegs, light them and see just how far way we land!

shokman

Okay all great info but alas out of desperation I had to do something quick so stopped in at the local solar guys place yesterday and got talked out of LGP! His take on them was definitely had to go outside! Which I was not prepared to do. So I ended up with 2 x 6volt lead carbon. With a plan to upgrade whole system no later than March. They were about 100 bucks per bat and he said I could add 2 more if within a year no problem. So the plan is to get a new metal roof on house in the next month or so and will add  4 x 400 watts panels that he sells and probably a new inverter can’t remember if he recommended 24v inverter? I would like to probably add everything this fall as I’m concerned about adding batteries old to new from everything I have read on here. I like the idea of the LC as no need to maintain water level and was quite concerned about getting 130lbs in and out of hole but got creative and put a screw hook in ceiling and used a block and tackle to raise up and down lol. Batteries are Valiant brand. I could also use my existing panels but was told I would need an additional cc ? Something about lower voltage on old panels or classic 150 was not big enough kinda got lost at that point 🫢. What say you guys about all this ? 

shokman

Sorry first sentence should say LFP

shokman

And 100$ more per battery not 100 per as it sounds lol. Guess I should preview post as cannot find edit feature 😳

SteveK

Glad your local guy could help. Lead Carbon (VLRA, ALC, AGM) type batteries have their merits. Your guy now has more information than we have so I can only assume he suggests you add a second charge controller to handle the new 400W array of panels he will sell you so you don't need to match new panels to your old panels. You will most likely end up with two charge controllers charging one battery bank. No problem there. It would be best you had both identical and compatible charge controllers that can synchronize their charging cycles but it not required to do so.

There is nothing about any of this that a Midnite Classic couldn't handle. A second charge controller will simply maximize the benefit of your new and old arrays. And your local guy is there if his brand flakes out.

Happy you have a solution!

Edit: Edit feature is the gear symbol upper right corner.

shokman

All good, my only confusion is the controller thing. He does not sell the classic, and would sell me a much cheaper one mppt ?? But I'm wondering if I should just ditch the old panels as I'm thinking they would not be required too properly charge my 800 amp hrs once I add 2 more batteries ? He was going on about the classic 150 not being capable enough to support both sets of panels ? But I'm sure 4 x 400 panels could be handled by the classic. I'm also not to up on all the math as I believe the classic is rated for 90 amps and I think 150volts and have no idea what voltage or amperage the new panels would send. At present my 4 panels are hooked in series and parallel and if memory serves me come down at max 50A and the wattage is my best guess at around 50ish ? 
Marc

littleharbor2

shokman said:

All good, my only confusion is the controller thing. He does not sell the classic, and would sell me a much cheaper one mppt ?? But I'm wondering if I should just ditch the old panels as I'm thinking they would not be required too properly charge my 800 amp hrs once I add 2 more batteries ? He was going on about the classic 150 not being capable enough to support both sets of panels ? But I'm sure 4 x 400 panels could be handled by the classic. I'm also not to up on all the math as I believe the classic is rated for 90 amps and I think 150volts and have no idea what voltage or amperage the new panels would send. At present my 4 panels are hooked in series and parallel and if memory serves me come down at max 50A and the wattage is my best guess at around 50ish ? 
Marc

The classic 150 will put out up to 96 amps in a 12 volt configuration. That is over 1400 watts at full charge voltage.

SteveK

Sorry, not sure why I read a new 400W array instead of a new 1600W array. Must be my old brain again.

You started out only needing batteries. Now you are getting an entirely new system. Since you are fully opening up the coffers I would challenge this guy on the quality differences between what he offers versus what you already have. Names like Trace, Midnite (Classic) and Rolls Surrette (RIP) deserve that at the very least.

I would pause at a cheap MPPT charge controller but they are out there and many folks do use them with success. There are also many folks that reverse direction after the fact for names like Victron (<<these are great) Midnite and Schneider. There used to be cheapos out there with large coils, like Rouge made in North America, but now a days they seem to all be high-speed switching types. Not my favorite but I'm not everyone either. Done right they can be and are great....for a price.

Not sure why you would eliminate what you have but understand the desire. You can include some of that old stuff if you have the room. Can't really have too much panel, ya' know? I was most concerned with the old Trace...but the Classic? Never dawned on me. Until this June I used a "jurassic" Classic s/n 115. I still have it in reserve duty and intend to fit it to a second array.

I know one man's experience means naught but I operate over 5kW of panel on one Midnite Classic 150. If you get away from 12V and can do a 4S pack @24V with these panels it should be fine. Seeing as you a getting rid of the 12V Trace anyways.

But there is something to be said about "less is more", simplicity and asthetics too... Will stay tuned to see what you decide.

Good luck!

shokman

As I have been told before the the 920 watt array was not really enough for my old batteries especially in winter months. I may stop at new panels and the 4 new batteries 

shokman

I did install a mini-split ac that would be nice to run off the panels. It is a 110v 12000 btu

BB.

You should see an edit function behind the "gear" upper right:



-Bill

SteveK

shokman said:

I did install a mini-split ac that would be nice to run off the panels. It is a 110v 12000 btu

I do. Might as well take advantage of the summer months even though my system wouldn't keep up with this in less sun in wintertime while still supporting my critical loads panel. Here's the consumption of my 900sq/ft home cooled to 68 degrees by one 12k 240v 13 year old Mitsubishi. The two higher consumption days were over 90F and sunny. This is just the mini-split obviously.

If you are doing it now with a genny this is much better.

littleharbor2

shokman said:

I did install a mini-split ac that would be nice to run off the panels. It is a 110v 12000 btu

I installed a 1 ton 110 minisplit as well. Found out pretty fast my 2100 watt array would not keep up with it, my other loads and battery charging. Ended up putting up a separate array, dedicated to the minisplit alone.

SteveK

Hey littleharbor2, make us jealous. How much array did you need to add to support those Devil's Spawn temperatures while enjoying the gloriously abundant sunshine at your place in Baja?

For reference, I'm in Central New England, USA with an awefully shaded lot starting in October.

littleharbor2

Well, I got a great price on some 550 watt panels down here, ($250 a piece ), so I put 2200 watts up to power an 1100 watt load. I have two totally shot 12 volt agm batteries just as a buffer so run pretty much off the panels all day. Oh BTW I coupled this all to a 3000 watt 24 volt AIO inverter.
 That description of our temps and abundant sun is pretty much an understatement, lol, Makes for a long summer. The only thing I like about it is the 90+ degree ocean water. I have almost fell asleep a few times while bobbing around in it.

SteveK

1100W load says a lot. I rarely see more than a 250W load on mine except briefly on startup. I heat with mine in the winter too. Much bigger numbers then...

90+F water temp? I'd be sweating buckets in there and wouldn't even know it! lolol Sounds great though. Up here the ocean is usually a bit too chill but you get used to it.

We pull our small rv to Moab occasionally. It never ceases to amaze me just how much work we get done with one single tiny little 180W panel on the roof there.

littleharbor2

The 1100 watt number would be the max watts. I haven't actually put the clamp meter on it to check. I will today.
After living in the Pacific Ocean, Catalina Island, for 48 years, we felt like the 76 degree summer water temps were warm. I won't even get in the water now till it's over 80.

littleharbor2

Well, I was shocked just now. Not with voltage, with the current reading of my minisplit. It is pulling 14.6x amps @115 vac, 1660+ watts

JRHill

LH, why are you shocked? I'm watching this with interest, seriously.

I borrowed a 'cooling' unit from a neighbor that was brand new but it used too much power for his set up. It had the tubes to the window for in and out air and he wanted to sell if for $60 (new $400+). When I tested it with the Kill-A-Watt it got to 1300 watts and was still climbing when I shut it down. Nope, too much draw, I'm not going into the night with the batteries pulled down. Besides, the DW growled at me for even investigating this idea."Take a cold shower" she says. Good point. During the summer we have excess, unused generation but that is also when the well pump cycles a lot at 1100 watts plus the typical day to day use/overhead. So the minisplits are of interest to ME. The summers are getting hotter and one of these days when we are inside through the day because its too hot I may have to look into this deeper. So I have my antenna up.