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DIY Solar - LTO SCIB from Greentec Auto?

icthus77

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Aug 30, 2020
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Hi there!

I have watched a ton of Will's videos and searched the forums, but I haven't seen anything on these:

https://www.greentecauto.com/hybrid-battery/repurposed-batteries/20ah-lto-titanate-li-ion-scib

It is a LTO titanate battery, I think from a Honda Fit or Insight. 1.1 Kwh of Lithium Titanate batteries in two 12s packs. Comes as a 64.8V pack, can be reconfigured to 32.4V by flipping around one of the blocks. For the current price of $265 and free shipping this seems very appealing, I am thinking of buying 4 to build a 4 Kwh battery. I called the company and they said there is the original circuit board that they are calling a BMS.

I haven't seen any builds with these and would love to know your thoughts on how these might work as a 32v or 64v battery for solar. Would I have to buy a BMS or would the existing board work?

Thanks!
 
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I'd regard those more as 12*2.3 = 27.6V packs.

I would plan on your own BMS solution as those are likely designed to send a signal to the vehicle BCM rather than just cut-off, though they might have some balancing function.

With a suitable 12S BMS, I see no reason they couldn't make for a fine pack.
 
Great, thanks! Any recommendations on where to find a 12S bms? Or should I get a 24S and make a 55.2V pack?
 
Did you ever finish building your pack? What did you end up going with? I'm looking at these cells as an option as well. Thinking for simplicity of a 12s2p and get 2 daly 12s bms for LTO. Ideally I would like to build Yinlongs from scratch but shipping from China to Canada seems crazy expensive.
 
I picked up 6 of the LTO packs that Greentec Auto was selling. I originally paired it with a PIP-LV3048 MPP all in one solution but that failed after 2 weeks under some normal charge/discharge testing scenarios. Now I have it set up for 24v system 12s12p and it seems to be working well. So far, the cells are remarkably balanced. Staying within 0.01v even under 3c charge and discharge. I have installed balance leads on each of the 12s packs but I am using a single 1A 2s-24s active balancer from eBay to check in on them and balance down to 0.004v. I think I am going to watch them but it would be awesome if I didn't need to buy twelve 12s BMS for this setup.
 
I picked up 6 of the LTO packs that Greentec Auto was selling. I originally paired it with a PIP-LV3048 MPP all in one solution but that failed after 2 weeks under some normal charge/discharge testing scenarios. Now I have it set up for 24v system 12s12p and it seems to be working well. So far, the cells are remarkably balanced. Staying within 0.01v even under 3c charge and discharge. I have installed balance leads on each of the 12s packs but I am using a single 1A 2s-24s active balancer from eBay to check in on them and balance down to 0.004v. I think I am going to watch them but it would be awesome if I didn't need to buy twelve 12s BMS for this setup.
 
Nice, thanks for that information. Sounds like you have a nice system. I will probably regret not getting more of these, but just can't justify it right now.
 
I have 8 @ 12s Toshiba LTO packs that I've been testing while getting ready to hook them in a 2s4p configuration to replace a 8s @ 6v Pb solar battery bank. It's grid-tied so my main criteria for picking LTO was the ability to keep the cells constantly at a full charge without degradation.

So far in testing, with a half dozen charge discharge cycles, the cells are staying closely balanced. I'm not sure that I need a balancer for my use case. Maybe a cell monitor will be sufficient since I don't lose grid-power more than half a dozen times a year.

However, I have a 24s 100amp BMS that I haven't hooked up yet.

To avoid the rat's nest of cell monitoring/balance wires between the 96 cells, I'm making the parallel connections between cells with cables made of 12 wires @ 18 gauge wire and Molex male connectors at both ends. I'm experimenting with making my own circuit board using copper tape to connect the cell terminals to two Molex sockets for each battery. (One for the cable from the prior cell and one to the next cell.)

Photo of partial board attached. Those are 3amp glass fuses in the center. I'll tape down and cover the copper tape so that it doesn't come loose and to provide protection against shorts if somethings dropped on the traces. The female Molex connectors have been delayed in the Christmas mail so they're not yet present. The cables will be a lot of work--almost 400 pins to crimp and insert but it makes it easy to assemble on my work bench and then easily unplug and move to my battery box. 18 gauge wire is overkill but it's easier to crimp than thinner wire.

I'm using Anderson 120amp PowerPole connectors to make the power connections between cells--again so I can plug/unplug batteries. I got a good deal on them from Battery Hookup awhile back.
 

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