Score of a life time!

[XeonPony]

Well ones incompetence is anthers great fortune!

The story:

On a local auction site 2 Blue boxes came up, in those boxes were 384AH 80V lithium battery prototypes for some sort of industrial traction system, brand new in 2019 and not used since. Why would one has some thing and not use it?

When striping the packs down I discovered an interesting thing, top shelf components through out, but the most critical part of the battery securing the DC negative cables? 2 tiny cheap screws secured in the phenolic resin! That'll hold or so they wished! Clear signs of arcing and lose!

Interesting design, it used 3 24V racks at 384AH each, the BMS is very proprietary.

I selected the JK BMS ( B2A24S-15P ) based on a wide array of you tube reviews and experiences.

Cost: 3,200$CAD was the wining bid, but after nickle and diming it came to 4,200$ Canadian, Delivery cost 1 12" Pizza (Friend)
BMS was 200$CAD

The unit and racks taken apart:





Stripped Rack:

[XeonPony]

Stripped rack continued



Included was a nice array of parts!

[XeonPony]

Now I am starting to make a rigid frame for the battery

[XeonPony]

BMS and fuse system installed





So far the battery is in excellent health, from auction to basement running the house took 2 weeks, during that time I spend as much possible trying to figure out the cell type and chem, best I can tell it is either LCO or LMO

So I programmed it to that, I am following the 80 / 30 rule, I am amazed at the difference compared to lead acid, this was the largest gamble I have made in my life, and to get a winning hand is a life changer!





This is my first time with lithium, so if any can spot errors or improvements do please let me know.

[XeonPony]

Lastly I used some of the plugs it had come with, so should I need I can easily plug the lead acid bank back onto the system.

last thing will be to tidy up the wires and get the battery better situated down stairs and a heating system installed.

[SparWeb]

Congratulations on the discovery.  It's a great feeling to find an opportunity like that, even better when you can grab it!

[Rob Beckers]

If my math is right you have 2 x 384 x 80 = 61 kWh in energy storage there? That's a GREAT deal! Congrats!

What are you planning to use as an inverter? Or did they come with one (may have missed it reading through)?

-RoB-

[XeonPony]

If my math is right you have 2 x 384 x 80 = 61 kWh in energy storage there? That's a GREAT deal! Congrats!

What are you planning to use as an inverter? Or did they come with one (may have missed it reading through)?

-RoB-

I wish! I can only use 2 of the racks due to me running at 48V. I looked into what it would cost to make a matching rack so I could use the third one, but just to copy it would be about 5+ K!!!

So I will fix the defect on the 3rd rack, put a 25v BMS in it and sell it to recover costs, I can live with 300AH usable power for a long time given I lived with 115 for the last 3 years!

The stack is constructed 6P 7S (24v @ 384AH).  So in my configuration 6P 14S = 48V * 384AH = 18,432 Watt Hours, IF I could have cloned the rack I'd have apx 30KwH

Each 6 cell stack is isolated from the next, so it is pretty solid and safe construction. 384 AH is an odd number I end up with 64AH per cell.

I'm using my current inverter  3Kw, Pure sine wave, HF (No transformer), Built in 60Amp charger, built in MPPT (They claim 80amp capable, haven't tested yet)

I have used it with the welder, and air compressor and such, I am rather impressed with it.

[Mary B]

Some sort of fire suppression system is recommended... lithium in the house is something I would NEVER do due to fire risk

[XeonPony]

Ya, Halon 1211 comes to mind, and a fully sealed metal box with a vent pipe leading out side.

[DamonHD]

@MaryB my insurers had to be persuaded to insure my Li stuff *not* in the house.  In the end I managed to jam half of them in a locked cupboard in the shed under my 200Ah lead-acid and the insurers covered just those...

Rgds

Damon

[joestue]

haylon won't do anything.

5/8" drywall between each cell might prevent the fire from spreading from one cell to another, provided you can keep them cool.

a controlled water mist might do it. not enough water to short out the batteries and produce hydrogen, but enough to keep the thermal conduction through the drywall from lighting the next cell on fire.

[XeonPony]

haylon won't do anything.

5/8" drywall between each cell might prevent the fire from spreading from one cell to another, provided you can keep them cool.

a controlled water mist might do it. not enough water to short out the batteries and produce hydrogen, but enough to keep the thermal conduction through the drywall from lighting the next cell on fire.

Thankfully the battery maker did that all ready, each cell is in a protective box with high temp silicone isolators and flame guides. Apparently spear power system does military contracts and such

So the stack is very well done, it is mind blowing that the level of quality all the way up to the DC- cables been top notch then they hit the stupid wall and used a pathetic means of attaching the plate.

As for the Halon, dam, my main idea all ways was to duct the fire out side away from any thing flammable, and the center core of the battery would be the heater and isolation between the two stacks, Ultimately the goal is to move the whole power system to an out board shed.

Even the heating system, My long term plan is to only have the power cable and 2 pipes coming into the house! but for now I am enjoying not having to run the genset in the morning!

I`ll dig around and see what I got access to in terms of dry wall as that would make a suitable box!

[Mary B]

Use metal studs! Drywall will lose all structural strength as the paper burns off... it MUST be supported. For the outer box I would use poured in place concrete... vent to outside with a stainless double wall pipe like my pellet stove uses and a GOOD spacer around it of stainless to keep tat pipe well away form any wood in the wall. Use positive pressure on the box to force burning gasses outside. Pretty much how the first pellet stoves worked before they figured out it was safer to pull air thru the firebox with a very high temp blower. Pressurizing it was causing hopper fires... an issue you won't have unless you have cracks the burning gasses can escape thru. Wood stove gasket cement is very high temp and can be used on the wood stove gasket material around the door into it. I use it on the gasket to the ash door on the pellet stove and to replace the main door gasket when it needs it(about due... getting a whiff of wood smoke now and then)

[bigrockcandymountain]

Haha congrats on the awesome score.  I think i bid you up a bit on these, but not right up to what you paid.  I saw your name on the auction site and was pretty sure i knew who was bidding.

Saskatchewan is a small world, that's for sure.  I'm glad they went to someone who knows the value.

[XeonPony]

Haha congrats on the awesome score.  I think i bid you up a bit on these, but not right up to what you paid.  I saw your name on the auction site and was pretty sure i knew who was bidding.

Saskatchewan is a small world, that's for sure.  I'm glad they went to someone who knows the value.

Lol indeed it is! would love to find who bought the first unit, and either buy a rack from him, or very least explain the fault I found so he can use the unit, thought I recognized one of the names on that list!

Would be amazing to get a full 30kwH battery, but 300 beats the 115ah I been living off all this time! Now that I got a battery that can absorb it been seeing a consistent 1,800 to 1,900W from my array!

and last 2 mornings no need to worry about genset! some one did dirty and tried to snipe me, but I know that game and expected it!

If ya don't mind dogs sheep and a parts wear house should come by for a coffee some day!  Love to meet some more local off griders/ home steaders

[bigrockcandymountain]

That sounds great.  I don't get over that way very often but I'll keep it in mind.  You are welcome here any time too.  Here it's chickens and cows. 

[XeonPony]

That sounds great.  I don't get over that way very often but I'll keep it in mind.  You are welcome here any time too.  Here it's chickens and cows.

I miss Muffin, She was the pet black Angus heifer, raised with the dogs and became my friends wife's pet, she'd steal jerry cans and try and eat the weed wacker spark plug wire while you used it!

Next big road trip will give you a shout! Love to see what your set up is like.

[SparWeb]

XP,
What would it take to convert your spare unit to 3P 14S to make it 48V?
I can't see a way to split those 6-packs, in case somebody wanted to.

[XeonPony]

a very fine die grinder, lots of patience, steady hands.

they are laser welded, other wise in principle shouldn't be impossible, just a pain in the rear, I'll try and get a really good picture tonight.

[DanG]

That short circuit delay of 1-1/2 seconds would be weirding me out - that could be a lot of molten copper doing 1/10th lightspeed along strobing DC magnetic flux lines.

Can I tweak that to 1/4 or 1/3rd second, if the welder etc. inrush won't trigger it?

[XeonPony]

Well any short of concern the fuse will deal with that. Don't want the controller trying to do it, as due to tiny tiny differences in switching speed it ends with one MOSFet trying to hold the whole current till it too switches off, usually by vaporization.

So using the Semiconductor fuse, it will be isolated in picoseconds and I'm out a 300 dollar fuse, but BMS intact and able to use full rated capacity and no magic smoke being released.

Fuse is sized so that no load will ever come close to its rating ever, other then a dead short.

Next step is install a DC circuit breaker panel, with each rated to the load driven, so that any fault will favour the CB, befor the fuse.

I really wish the BMS had a signal out that can be put on a shunt trip CB, or contactor for fault protection as that way it isn't the sacrificial component.

[JW]

I hope you have scope meter or something to look at those live circuits, you can conduct without the Mosfet. I was working with a low volt 330amp mosfet array that I built. 

[XeonPony]

I saw some real world tests on you tube, and most had the same problem! In theory, with aggressive pull down circuit, you still have switching variances, so in the cascading shut down it can lead to only one or two carrying the full shut down flow of current.

The one unit was tested only one mosfet blew and unit remained functional.

The odds of a short is so low that fuse is the best fail safe followed by breakers to handle any normal system over load.

[kitestrings]

Prety cool.  Congrats.

Is the 'Dashboard' monitoring part of the package, or is that something that you developed, or adapted for another storage system?

[XeonPony]

part of the bms.

[XeonPony]

Well got a second one! so  I will share details.

Reserve is set to 5K but they are willing to accept as low as 2k. There is at min 1 more remaining.

McDugal Auctions in Saskatchewan

they will need to be dismantled and the dc negative terminal plate drilled and taped and bolted on.

[SparWeb]

It seems to be gone already

[XeonPony]

It will be relisted

the one I won it was updated with the max bid I put in and they accepted.

Auction closed at 369 dollars, obviously guy laughed at that, but they phoned and asked if I would put in the max that I bid and they accepted.

So keep close eye on there, may be a couple more yet.

The unit I got was pretty well virgin with no usage, cells are in perfect health, I turned off active balancing as a test and this whole week it has been .003V deviation!

I'm guessing that bad DC - connection caused em some head achs or the project just got shelved shortly after getting made.

But at 55KwH of storage I think I'm set for a very long time for battery!, now is just making a better home for em, and getting a warmer built for winter!

Top shelf components in the BMS and the box is a beast, 1/4inch plate steel powder coated! Charger is 6.6Kw CAN Bus programmable charger (Out side my ability to use, worth 2 grand new, I was / am going to try and sell them at 1k after testing to try and recoup some money as I am now - dollars across the board!)

If far out any one who wants to put a bid on it I could store it here for ya (Further info by pm if you go that route) , as I am 250km from location, and have space, just if it sits it may come with added wool from the sheep rubbing on it! But more than happy to help out.

[Bruce S]

Way too far for me, but I did like the idea of extra wool!!
You might reach our to DamonHD about the CAN bus programming, he might know a thing or two

I've been trying to get a Prius or Leaf castoff battery pack or two.
Those bugger went through to ruff in cost around here (USA Midwest)

Come to find out a company located in California has been buying them up. They built a PEAK storage grid unit out of 1000s of these.

Guess I'll go back to recycling laptop batteries, funny how none of all the ones I tested have more than 85% capacity still in them.

Cheers

Bruce S

[DamonHD]

No CAN do here (!), but the little I know about MODBUS (to talk to my Morningstar solar controller) is here:

https://www.earth.org.uk/RPi201406/code/mbaccess.h
https://www.earth.org.uk/RPi201406/code/mbaccess.cpp

(and libmodbus, see the makefile).

Rgds

Damon

[XeonPony]

I never got into soft ware, I'm a hard ware only guy sadly, so wouldn't help any ways.

Besides I got a charger all ready these units way over kill for me on top of the issue of I have no way to talk with them, leave that to more knowledgeable and skilled people.

They're Virgin 6.6Kw chargers, hate to cook it where some one ells can enjoy it for half the cost.

[SparWeb]

Ha, well now there's an electric airport tug there, with its own 48V battery (flooded lead).  I'll keep an eye out!

Thanks again!