Small Cabin

Small Cabin Forum
 - Forums - Register/Sign Up - Reply - Search - Statistics -

Small Cabin Forum / Member's Projects and Photos / Creeky's lithium battery build
. 1 . 2 . 3 . >>
Author Message
# Posted: 4 Jun 2016 08:59 - Edited by: creeky

Breaking news

Creeky's new lithium battery pack]Creeky's new lithium battery pack

I've been talking about lithium for some time now. It's just a better battery. Well. I've taken a calculated gamble. I found a 2014 chevy volt battery from a wrecking yard. Untested.

The nitty gritty?

The wrecking yard in far far far north Quebec was nice enough to deliver the pack 1/2 way to my house. They drove for 3.5 hours south. I drove 3.25 hours north. We met. Slid a pallet between two truck beds.

I drove home thinking. Please be 3. 2.7 and I just spent something short [yes the electrical puns will be many] of $2k on some fancy packaging. It's a gamble. No way to test it.

Needless to say. First thing I get home. Tractor comes out. Fork lift bars go on. Pack gets carried to the tractor shed where it will reside while I work on it. I get the lid off. Out comes the voltage meter.

Front pack. 115.3v or 3.84 /cell. Middle pack. 92.1 or 3.84 / cell. Back pack. 161.4 or 3.84 / cell.

Huge sigh of relief. Minor dancing in the field.

So I now have a 2014 pack basically fully charged. All I need to do now is take it apart. Build/find a bms solution. Reconfigure my Morningstar solar controllers. Buy a Victron 48v inverter. And a few other dozen things.

But that's a job for tomorrow.

Am now taking suggestions for BMS. I wouldn't mind trying an arduino ATtiny something. Anyone with ideas?

Back to dancing in the fields.

(Thx to Steve_S for suggesting I make this a separate thread from my camp build.)

(And, as always, there will be considerable additional material on my blog. Photos. Details.)

Stay tuned folks.

# Posted: 4 Jun 2016 09:11

This one is tagged and being watched now... always up for a learning experience (especially one that won't cost 'me' cash... as that is in short supply, LOL)

# Posted: 4 Jun 2016 09:51

The next morning.

I go out and look at my purty battery in the morning sun. I have a cup of java in my hand. Life is good.

The plan:

After much deliberation I will break the pack into 48v sections. I could break it down to 12v. But if I'm expanding my storage I should probably look to future. If I go 48 I can add 4 kw of solar panel to my current (see told you) 2 kw. Huzzah.

The chevy pack comes with 7 48v battery sections and 2 24s. At the moment I plan to use at least one of the 24s (1kw ea.) for my solar boat project.

I am still debating whether to go 5 48 sections for 10 kw storage. 6 for 12. 7 for 14. Usable that means something around 6.5/8/9.5 kw.

I will use my morningstar controllers with a custom charge profile. The absorb will be set to 49 (4.05 cell). The time will be 10 minutes. I will then set a float value of 3.8 or 45.6.

Full charge on this chemistry is 4.2. Uh oh is 4.275. By leaving the charge at 75-80% max I should extend the life of the pack.

Discharge max will be 3.2. The Victron 48-1800 has a low voltage cut off of 38. That's a value of 3.17. Perfect. This leaves a rather huge "knee" of power in the batteries. Again. Should extend the pack lifespan.

This will be the safety net for my batteries.

I am also debating what kind of bms (battery management system) I will install. Do I do just balancers? From what I've read these devices are inexpensive and useful? (A balancer circuit uses available pack power to make sure all the cells in the battery pack are at the same voltage. Usually by draining a bit of power from higher cells.)

Or do I go with a basic monitoring system. Read cell voltages and temperature. Track them. Adjust manually as and if required.

(Considerable experience in lithium on line reflects that the cell voltages, once balanced, rarely drift out. And remember. Because I have such huge knees, even if one cell drifts a bit it will still be within the safety range.)

Or do I go all out. Auto balancing, tracking, monitoring all in one. Needless to say this is the most expensive option. And BMS solutions from reliable mfct range over $1k.


In all likelihood I will have at least one 48 (2 kw) for sale. Offers? Eastern Ontario only as there is no way to ship. Must be picked up. Contact through my blog.

I will also be selling off one 5 year old FLA. 6 batteries. 1185 ah@12v. Good condition. Surprisingly good actually. It's just a bit too small for my needs. Electric fridge, cough, cough.

A 12v charger. 75 amps.

A TBS 12-1600. Probably the best inverter in the world.

# Posted: 4 Jun 2016 09:52

Steve. I just saw your post. How'z the build going? I certainly hear the lack o'cash. My build has gone through a couple of those. smile.

# Posted: 4 Jun 2016 10:16

Just a few posts from other folks doing lithium car salvage.

this guy is amazing. uses a Leaf battery pack (now 2)

this guy gave me the knowledge that I needed to trust the Chevy Volt solution could work for me

This guys porsche build was neat. used a 'spensive bms tho.

not sure what this guy is up to. But it's an interesting build. he does some stuff I don't clearly understand. but it's a 12v 800 ah lithium build. he's gonna rock it for many a year to come.

and this is the tear down on youtube that showed me what was what.

I have also found schematics etc. But those we'll file under tmi.

# Posted: 4 Jun 2016 11:31

Congratulations on your find. I'm curious to see how it all works out for you and hope you keep us updated. I can't answer any of your questions specifically, but in general, I've found the KISS philosophy to be a good one.

# Posted: 4 Jun 2016 18:50

@ Creekster: Last year I had major health / medical issues which pretty much blew my year of productivity as I could barely walk most of the year... I fortunately crossed the hump over winter and am able to walk now without major pain or assistance so I am slowly getting "back in the groove" and holstering the hammer. Building resumes next week and will be on an "easy pace" so I don't over do it or push myself to the brink of long term injury again. I'll start updating my Build Thread in small spurts as I can but it will be in chunks as it happens.

BTW: More Mennonites have moved to my region over the past year and now we are getting all sorts of quality goodies coming avail... from fruit & veg (always the best) to builder's (Cabins, Sheds and more) and even one of them started a Truss Factory. Sure is good to see the old farms that had started to go fallow being worked again and properly being brought back to production... In many way's I admire (even envy a bit) the Mennonites and their way of living in cooperation with Mother Nature.

# Posted: 4 Jun 2016 21:28 - Edited by: Julie2Oregon

Wow, Creeky, that's AWESOME! Congratulations!!! You're brimming with battery power now! And working on this yourself, you know exactly what you've got, how to work with it, and build/configure precisely the whole solar power system you want. That's truly excellent.

Btw, there's a part of me that, after all of the reading and pondering I did, is a tad disappointed I'll be doing grid-tie. From a financial and ease-of-use standpoint, it's great but I did want to be independent of the grid and more in control of my electrical system and needs. Ah, well. I've gone lithium with my lawn equipment and tools so I guess there's that.

# Posted: 4 Jun 2016 21:54 - Edited by: creeky

Quoting: Steve_S
I admire (even envy a bit) the Mennonites

I'm with you there. Something to be said for shutting things down and living slower. This summer I started a policy of turning off the internet at 8 (don't look at the time this post was written).

Funny but it makes a difference. Sue plays her guitar more. I write and listen to the birds. It's nice. Sadly it's largely due to the ebbing battery bank. I worry that when the lithium goes in the internet'll be on all the time. Or I'll start watching a lot more TV.

Good luck with your health. And glad to hear you're on the mend. Us old guys. We're in no rush, except to have good lives. I have to take it pretty easy too. These old bones ain't so spry anymore. But it's not a bad thing.

Btw. I'm a mennonite farm boy from Saskatchewan. Way back when.


I'll add a few pics of the unload.

Here's the pack in the back. Of my truck.

Eagles are landed

It was a bit tricky. The biggest battery was at the wrong end. I could slide the pallet in the bed but the tractor couldn't lift it. Finally, after three or four adjustments to the forks and then running the revs to the line. I got it up an inch. and very. very. very. slowly and carefully backed up and took it to the shed.

Lithium pack is out

Huzzah. Al pays for himself again. Always good to have a buddy who can lift 500 lbs with his two iron arms. Tho they're getting a bit droopy as I head into the tractor run in.

After a good battle with the cover. Here's a pic testing.


As always. There's a bit more info at the blog.


Thx Julie. It's more about having fun for me. You know. When you're an old fella like me. you gotta keep learnin' new stuff. Or ya start wandering the fields and thinkin' there's somethin' you forgot. Like take time for instance. Seems to move right along doesn't it?

Ontario lakeside
# Posted: 5 Jun 2016 00:31

creeky. amazing stuff. can't wait to see how it goes together.

# Posted: 5 Jun 2016 07:33 - Edited by: Bret

Hhmmm, our 2008 Prius is starting to look alot like the pig at breakfast. BACON! I mean batteries.

# Posted: 5 Jun 2016 12:46

Those red caps on the end (lower left hand corner of photo), are those plugs for coolant lines?

# Posted: 6 Jun 2016 18:11

Mmmmm. Bacon. Dang. Now I'm all hungry. (Did you see Sue's Prius in the pic? way off by the studio)

Yup. those red caps cover cooling/heating lines. The plate at the front contains (according to research), 2 contactors and a heater that runs off the battery pack. I have yet to open it.

I did find a Scandia presentation about the ESS they built with Chevy Volt batteries. They dropped the liquid cooling and just went with air cooling. I'm assuming due to the lower current draw. I need to heat in the winter. I'm thinking maybe repurpose? Insulation first of course.


I've found a couple of BMS solutions that are fairly reasonable. From China. Blush. But at 40 x 6 = 240 vs fancy 1000 and up versions. Might just dabble in a bit of that.

Can somebody help me with my math?

Okay. I have a 48v battery pack with max 2500w loads (surge off the fridge if the dishwasher/vacuum is running).

So 48v @ 2500 w is 50 amps.

Now I divide that between my 6 parallel packs and I get 8 amps per circuit? Call it 10.

Double that as I will probably add another inverter as my next step forward. 20 amps max discharge?

So I could use 35 amp bms boards? Makes a big difference on cost. Lower is cheaper.

Man my brain is foggy lately. Must be summer.

# Posted: 6 Jun 2016 18:33

looks like 35 amp boards would be more than enough.... good safety factor.

# Posted: 7 Jun 2016 10:35

Thx MtnDon.

I've been looking at different BMS suppliers

Supower. No documentation. Few reviews that I can find. 60 bucks a board at 60 amps delivered to my home. So 360 for the base BMS.

bestekpower has some BMS with communications boards. very poor documentation which ... but good reviews amongst the EV community.

great reviews. lots of users. good documentation

No word yet on price for the last two.

Fingers drumming on table. Dang. Hard to be patient once you have the pack sitting there.

# Posted: 10 Jun 2016 15:58

Tear down begins.

Can't begin to express the pleasure I derive from taking something so beautiful apart. Really put together so nicely. And all the bits and bobs are so well thought out.

Somebody's missing a tooth

Basically it was: take the connecting power cables off. Negative first! Disconnect the various control/BMS lines. Disconnect the cooling/heating hoses.

I take the smallest pack out first. So that's 2 48v packs tied together for 96. I test. The battery is at 92. It has dropped .1v since I first tested. I take the plastic cap off. Each cell tests at exactly 3.83. That's .01v lower than my initial bulk measurement (all cells together / 24).

Top popped

This also lets me know that the cells are balanced. Bonus.

I then fiddle the lock down. Wow. Nicely done. And with only one bleeding knuckle I lift the pack out. Carry it to the bench. Battery on the bench baby!

Battery on the bench!

Man. I can lift 4 kws of storage power. And look at the size. Still. I was breathing pretty hard after the lift and carry. Smile.

Oh. And REC BMS pricing comes back. Around 470 Euros. Or 700 Canadian. Okay. Not bad.

# Posted: 14 Jun 2016 22:24

Well. Good news.

After a great discussion with Joe at Morningstar. A read of new documents on the morningstar site. I have a controller programmed for the new lithium chemistry. Huzzah.

Of course, its programmed. But tested? Well.

It's sunny tomorrow. And I do have two separate controllers. So I've disconnected the second controller from the 12v battery pack.

Flashed the new program to the controller.

And hooked it up to one of the lithium packs. (Unfortunately one of the packs seems to have a low cell. Of the 24 cells, 23 read 3.83 or 3.84. Cell 12 on pack 1 reads 3.68. I will wait until I can balance that cell voltage before charging that pack.

Still. Looks good for test #1.

Fingers crossed.

And here's the controller reading the voltage from the Volt battery. All set.

Test #1

It will be interesting to see how much power is required to bring the voltage up to 48.24. (went very conservative).

# Posted: 15 Jun 2016 10:44 - Edited by: creeky

Okay. Test #1 complete. A complete success. At aprox. 10 a.m. my batteries reached 48.26, went into absorb and then float. The Tristar rules!

Unfortunately, duty called, and I missed the "absorb" phase. I have it set for 15 minutes.

This is tough as I was hoping to track the amperage at which it went out of absorb. I had thought the % of amp charge it went into vs exited absorb might have indicated the level of charge attained.

However, the voltmeter reads 4.02 on all cells. This is the exact setting I had hoped to attain.

Huzzah. Huzzah. Huzzah.

It appears that it took a titch over 700 watts to charge from 45.83 to 48.26. Very interesting given that it is a 2.2 kw battery. So 3.83/cell was basically at 50-60% charged. I think my 4.02 is about 80% charged.

And, I'm a bit "wowzah", as a .2v cell voltage change indicates 700 watts of storage. When I multiply by 6 packs. That's 4,200 watts of power. Or two full days of use for me.

Now to find the right inverter. Finish tearing down the pack. Charge up the batteries. Top balancing to 4.02. Yar. Matey. Grab your cutlass we're going overboard.

PS-as the charge seems to have balanced the cells. I am going to try the out of balance pack tomorrow. maybe. See if the charge improves the voltage discrepancy between cells. Again. Triple checked this a.m. All cells but one read 3.83. One reads 3.68. Dang.

# Posted: 15 Jun 2016 14:10

Thanks for giving us the play by play.

Do you still need a BMS now that the Tristar is configured for lithium?

# Posted: 15 Jun 2016 15:24

Glad yer all enjoying the ride.

The voltage has settled to 4.008/cell. smile.

Tested all the other cells. Every single one goes 3.83 or 3.84. Whew. Only the one wonky cell then.

re: BMS
I think I need the BMS for balancing. But I'm not going to install one right away. I ordered a Victron 48-1200 inverter. It has a LVD at 38v. So that's right around 3.2. Which is as low as I would care to go.

High voltage cut-off comes from the Tristar. As that's the only charge source that should be okay.

The tristar also has very good voltage sensing. So I'm pretty happy with that.

So you're right MondayCreek, I have managed two of the BMS functions. Now if I can get the Chevy Volt/LG balancers on the battery to work. That would be beauty.

Boy. I had thought I would commission this set up in September but everything has fallen together quite nicely. July?

# Posted: 16 Jun 2016 12:39

Well. The Tristar just completed charge test #2.

I charged two 48v packs today. Took 1370 watts. Or 685 watts per battery. Within 25 watts of the one pack test.

And pretty much can be explained by the energy draw of the Tristar itself. The -60 uses 1.7wh max with 1+ for ethernet. So call it 75 watts a day.

Man those batteries are close. And they've been sitting for awhile. Neat.

Here's the pic of the day. I found the second piece of the BMS. Now what might those big green things be?


# Posted: 16 Jun 2016 12:56

Also: Time to put in the obligatory warning.

Please kids. Don't try this at home. I am not a great electrician but I have some experience building solar/electrical stuff. My dad was an electrician.

These batteries are high voltage / high amps. They can output power at exceptionally high rates. A dropped metal some'at would vapourize the metal causing severe burns or death. Turning yourself into the resistive load would not be enjoyable.

Nobody wants their last thought to be. Oh. that's what the smell of my eyeballs boiling in my skull is like.

Wear protective clothing. Take extreme care...

If you don't know what you're doing. Don't.

Now go outside and play.

# Posted: 17 Jun 2016 22:06

Update: Will be quiet on the Lithium front for a bit. Job came in. Dang. And just before Canada Day. Also sold off some of the pack to pay for the project. Sniff. Tough to see them grow up and move away.

Left the second batch on the charger overnight and today.

2 things to note (for techies):
They charged 180 watts to get back to my "full" charge state.

So that controller along with the ethernet running is using more power than I thought. 1.7 (TS) + 1 (E) x 24 = 65 give or take. But the manual says ethernet can cost up 2 w/hr. redo the math = 90w/day.

Also, for reasons I am unsure of, but perhaps due to the algormarythmic nature of solar controllers (yes that's a new word from me;), the controller may be adapting to the setting I gave it (48.26) to the settle back after charging voltage of the battery.

The solar controller charged to 48.33 today. Interestingly the battery voltage settled back to 48.26.


I have a bunch of toys coming in. An energy meter and shunt (voltage amp counter); a marine switch for temporary charging; a cell log 8M, for reading cell voltages to .00X.

Rational for the energy meter.
My tristar controllers tell me how much power was made "in". But I've never tracked the amount of power going to my inverter "out". With the "bayite" energy meter and shunt I'll be able to track the power going out to the inverter. It'll be a fairly accurate guide to how much power is left in the system to use for those cloudy early winter weeks.

Why didn't I get one before, you ask? Because energy trackers typically cost over $200 bucks US.

How much did this one cost? 20 bucks. With the shunt.

Well. Enjoy the lovely weather. Think of me toiling over a hot computer.

# Posted: 20 Jun 2016 10:25

good read here creeky. I am going to be checking in from time to time to see how your setup is doing. I probably have a year, maybe two left on my FLA bank before I will be needing to replace it. I have a Morningstar MPPT 60A so this is of interest to me. Any thoughts on enclosing the bank in some sort of metal container for fire protection should something go wrong with the battery? That's one of my concerns with the lithium chemistry.

# Posted: 26 Jun 2016 09:28

Thx Dillio. You do have to watch the chemistry. For most, exploding Lithium batteries is pretty much "myth" territory. Obviously it happens. But all batteries have "explosion" stories. So does gas. So does propane. Etc. So ... you take care. Keep your voltages at safe levels.

(LifePO4 is of course the safest battery. My LiMn etc are a bit more tempermental. But the "hot" batteries tend to be the high storage/gram in cell phones etc.)

My latest experiments are posted on my blog. I'll share a few updates.

The ammeter/voltmeter is in. (18 bucks from China. Sheesh.) Now that I can track the energy going out. Its time to do some load testing.


I got right to it with "movie night." I took one 2.125kw battery at 48v. (Seen here at 47.8. Note the 11.9 w load. That's 10.4 wh for the inverter. And 1.5 for the TV "off.")

Hooked up the Victron 48-1200. A bit underpowered. I would have preferred something in the 1800 range. Will have to watch the surge/load scheduling.

Watch chick flick with the girlfriend. "My summer in Provence." Pretty good acting. Nicely constructed.

Discharge 518 watts. TV runs, depending on light in the shot, up to 260w.

The next day drag the battery out to the charge shed. Hook up. Test.

Load test complete

As you can see the initial battery charged was a bit low. This can be explained by the fact it was the first battery charged with absorb at 15 minutes. And the battery then sat for two weeks. Additional factors: Self discharge. Overnight solar controller load.


So 650 watts refilled the battery. Factor in topping up to a higher voltage (48.2). Add in solar controller load. All adds up to a very efficient system.

Interesting here:

The absorb phase is now set at 30 minutes. The battery charged in about an hour to absorb. My pollen cloaked panels staying in the 550wh output range. Once the V hit absorb at 48.33, the watts going into the batteries immediately drops to 250. Over the process of the 1/2 hr absorb they dropped to under 30 watts.

I couldn't watch the whole 30 minutes. Though it is riveting entertainment. But it does speak volumes about how efficiently the lithium charges.

It also confirms to me that 30 minutes is a good absorb period. I could go to an hour. But at 30w. Really?

PS-there's a post on my blog about how I finished assembling the battery pack. And more pics/detail. For those interested.

# Posted: 28 Jun 2016 14:23 - Edited by: creeky

Just a quick update.

I'm going to replace the battery cables. So today I build some 6g battery cables.

This means I have 12 2g battery cables for sale if anyone is interested. Lugs on one end only.

I plan to decommission the lead acid tomorrow? I have done the final equalize. I have to say. The lead acid continue to perform as per spec. 5 years was my dream lifespan. I had amortized for 2, with a hope of 3. So considering the loads I run, etc. Pretty good performance.

I am tempted to keep the system for an out building or some'aat. But really. Better to pass it along.

Okay. And I've solved the BMS equation. It was one of those lovely "ah ha" moments. You know. That moment when a body of information read about and perhaps perceived in an academic sense suddenly goes, clunk clunk click, and you see something you hadn't seen before.

It will mean a spot of wiring. Soldering. Probably should look for some speciality plugs. So I will leave the details for another day. But. Huzzah!

Hint. I will only need 1 BMS board. Ding!

PS-18 days of charge testing. All the batteries are charged. All the systems are operating as specced.

Ontario lakeside
# Posted: 28 Jun 2016 21:22

Creeky. if those lead acids have some life left I would be interested. we are still running on 100w of solar and 2 17Ah batts!

# Posted: 28 Jun 2016 21:55

Ontario. The Batts are very good. Very well maintained. I have an ad on kijiji. Search crown 395. Or contact me thru my blog.

Anyone interested in the tbs inverter?

# Posted: 30 Jun 2016 08:21

Well. My cell log 8m came in.
I really have to pay more attention to the videos I watch.

I saw a guy hook one into his chevy volt battery (or so I thought) and get all kinds of info. But, ha, it turns out he built a custom breakout board. Which he sells. $80/ea.

I had hoped to be able to read 8 cells at a time. to .xxx v. but instead I can read 1 cell at a time. still, to .xxx v. while my voltmeter only does .xx v. Yippee.

Time for a photo. Battery box under construction.

Battery box

Keeping with the recycled theme. This is the pallet the battery came on cut up with strips of plywood left over from another project.

No doubt it fails the lateral fixity code for off grid solar installs with repurposed Volt battery pack remnants. Subsection B4U.

# Posted: 30 Jun 2016 23:06


Well. It ain't pretty but it's up and running. This post comes courtesy of lithium stored electrons.

Huzzah! And happy Canada Day to all!

. 1 . 2 . 3 . >>
Your reply
Bold Style  Italic Style  Underlined Style  Thumbnail Image Link  Large Image Link  URL Link           :) ;) :-( :confused: More smilies...

» Username  » Password 
Only registered users can post here. Please enter your login/password details before posting a message, or register here first.