diy solar

diy solar

LTO SCiB battery bank for off-grid

AmpLee

New Member
Joined
Jun 1, 2020
Messages
50
So I’ve been parsing through the internet to find info on this battery technology as there are some used Toshiba SCIB units available on e-bay. There's a lot to like of LTO technology if you can overcome some of the hurdles. The hurdles seem to be price, BMS, space, and odd voltage attributes. Physical space to store the batteries isn't an issue for me, and while price for used LTO cells are expensive, I believe that their exceptionally long life make them fairly affordable spread out over time.

These particular cells have an on board BMS but it seems no one has figured out how to get it to balance the cells, so if you want cell balancing then you'd need to get an external BMS for every 24 cell battery (1.1kW). In a 40 kw battery bank that would amount to 36 separate BMS. So my question is, are BMSs necessary with this technology and if not, how would I be able to operate my system without one, and what downsides would there be. I guess I'm wondering what are the options here?

The other thing that seems to be a negative is that these batteries have unusual voltage attributes. It looks like there is 48v MagnaSine 4000W inverter that can handle the voltage range of the batteries, but I'm not seeing any other inverters that can both reach the upper and lower ranges. Is being stuck with this inverter a deal breaker? It's a pricey inverter, but it seems that installing a couple of these would allow me to use shop tools and water pumps. Are there any thoughts to this particular inverter or use of inverters with LTO batteries.

Lastly, I'm just hoping to learn more about working on these cells. I'm not very experienced with working with electricity or storage, so I'd like to know if I'm biting off more than I can chew by building a 40kw/h battery bank with these cells. Thanks for any input.
 
I took a quick look at LTO cells and found the voltage profile too difficult to work with when trying to find compatible equipment. Not just the BMS and inverter, every other piece of the build would be difficult to find. If you are really committed I am sure you can make something work but I doubt it is worth it. Just my $0.02
 
I took a quick look at LTO cells and found the voltage profile too difficult to work with when trying to find compatible equipment. Not just the BMS and inverter, every other piece of the build would be difficult to find. If you are really committed I am sure you can make something work but I doubt it is worth it. Just my $0.02
What other aspects of the setup would be difficult due to the voltage. I’m starting from scratch, so would be open to making it work if it weren’t too difficult.
 
I use LTO exclusively on my two systems and have no problems at all with the voltages. I use a midnite solar charge controller no issues with the voltage range. I also use a Samlex EVO inverter on one system and a Reliable energy inverter on the other system. The samlex can be programmed for the voltages quite easily. The Reliable can not be programmed but has no problems whatsoever with the voltage range I give it. High 31V low 23V
I run 12s configuration. The LTO cells have a usable range of 2.8V to 1.9V. I set the SCC for 31 volts and have the Chargery BMS stop charging if any one cell reaches higher than 2.79V. I do recommend a BMS overcharging these things is the worst thing you can do to them. If i was to get the scib packs I would reconfigure to a parallel series system so as to use 1 bms or maybe make 2 banks and use 2 BMS . I have been quite happy with my results. I use Yinlong cells below is my 3p12s battery

0426202204a.jpg
 
From my research I think the magnum inverters will also work well as they have a nice wide voltage range. But you can add or remove cells from a series to adjust the voltage range. I picked 12s over 11s because the layout just works better.
 
I use LTO exclusively on my two systems and have no problems at all with the voltages. I use a midnite solar charge controller no issues with the voltage range. I also use a Samlex EVO inverter on one system and a Reliable energy inverter on the other system. The samlex can be programmed for the voltages quite easily. The Reliable can not be programmed but has no problems whatsoever with the voltage range I give it. High 31V low 23V
I run 12s configuration. The LTO cells have a usable range of 2.8V to 1.9V. I set the SCC for 31 volts and have the Chargery BMS stop charging if any one cell reaches higher than 2.79V. I do recommend a BMS overcharging these things is the worst thing you can do to them. If i was to get the scib packs I would reconfigure to a parallel series system so as to use 1 bms or maybe make 2 banks and use 2 BMS . I have been quite happy with my results. I use Yinlong cells below is my 3p12s battery

View attachment 14429

Nice! Is there a thread with more pics of your builds?

Edit: I've looked around and seen some of your posts in other threads but wasn't sure if there was a dedicated thread to your use of LTO batteries. Also, thanks for the info!
 
Last edited:
I use LTO exclusively on my two systems and have no problems at all with the voltages. I use a midnite solar charge controller no issues with the voltage range. I also use a Samlex EVO inverter on one system and a Reliable energy inverter on the other system. The samlex can be programmed for the voltages quite easily. The Reliable can not be programmed but has no problems whatsoever with the voltage range I give it. High 31V low 23V
I run 12s configuration. The LTO cells have a usable range of 2.8V to 1.9V. I set the SCC for 31 volts and have the Chargery BMS stop charging if any one cell reaches higher than 2.79V. I do recommend a BMS overcharging these things is the worst thing you can do to them. If i was to get the scib packs I would reconfigure to a parallel series system so as to use 1 bms or maybe make 2 banks and use 2 BMS . I have been quite happy with my results. I use Yinlong cells below is my 3p12s battery

View attachment 14429
wow that is what I was looking for. I loved the fact that the LTO would pretty much last 10-20 years.
 
On my mpp solar lv2424 I have a low DC cutoff of 20v and the highest it can charge at is 29.2 .. so I guess it could use as a 11s, unless there is a better sweet spot for these cells
 
either way is fine 11s may work better and you save a few cells. I am very happy doing it either way. 90% of the energy in the cells is between 1.95v and 2.4v. 75% is between 2.31 and 1.98 this is my data from testing over 200 cells

So my point is you do not need to reach the max V of 2.8 or go as low as 1.6
 
That's awesome.. any recommendations on where I can price shop some?
 
Check Ebay for the SCIB cells. For the yinlong cells I have 150 on order and will be placing another order soon. I test them all and then sell them on eBay but give discounts to forum members. You could also add to one of my orders as well if you wish. These are not cheap though the 45Ah cells retail for $70 each on ebay in a set of 6. That includes shipping.
 
Check Ebay for the SCIB cells. For the yinlong cells I have 150 on order and will be placing another order soon. I test them all and then sell them on eBay but give discounts to forum members. You could also add to one of my orders as well if you wish. These are not cheap though the 45Ah cells retail for $70 each on ebay in a set of 6. That includes shipping.

I just put in an order with Greentec Auto for 40kW of SCiB batteries. You'll get a better price if you buy directly from them. Each kW is about $265. I'll keep folks up to date on my experience putting these together in a system.
 
Since the cells of the SCiB battery are already in series, you either have to have many BMSs which at $45 apiece (That's what DavidPoz got his for) can get pricey in a bigger system like mine. But, it's not too complicated in a 12s or 24s setup providing you have the right inverter.

On another forum, a poster mentioned that the SCiB cells can be wired to a fuse block (the most common of these is for boats) which both gives you cell level fuses and parallels your pack. I haven't looked into that method, but it seems like it could be a viable alternative. Any thoughts?
 
yes there is another member who had done it this way. I am not a fan of that many BMS so I would break the packs up and rebuild if possible. But I get it that that may be a pain.
 
I just put in an order with Greentec Auto for 40kW of SCiB batteries. You'll get a better price if you buy directly from them. Each kW is about $265. I'll keep folks up to date on my experience putting these together in a system.
40kw!
 
yes there is another member who had done it this way. I am not a fan of that many BMS so I would break the packs up and rebuild if possible. But I get it that that may be a pain.

Do you have a link, member name, or keywords that may help me find a thread on that particular build?

When you say break and rebuild, if I stay in a 12 cell configuration, I can leave the cells in their casing and I'd only need to cut the bars connecting each cell in series?
 
Do you have a link, member name, or keywords that may help me find a thread on that particular build?

When you say break and rebuild, if I stay in a 12 cell configuration, I can leave the cells in their casing and I'd only need to cut the bars connecting each cell in series?
Members name is @fisherus he has been busy so he has not been around a bunch but you could probably PM him to compare notes.

Yes I would leave cells in their case and rearrange the connections to a parallel then series config. I looked at the batteries online but i really dont know exactly how they are laid out in there original configuration. I think those are 20Ah cells so maybe you could do 6p2s in each box and put 6 boxes together for 1 battery. That woiuld give you a 120Ah battery for 1 BMS which is what I have with my Yinlong cells and it works fine.
 
Back
Top