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Discussion Starter #1
Or are they kinda old tech and there are better options?
pros and cons as i understand them and PLEASE CORRECT ME if these are wrong:

pros:
  • pretty modular, you can split the big T packs apart into relatively small modules and wire them together
  • module footprint is a "log" instead of a "tray", meaning you can put them in more varied places in a conversion
  • pretty well understood electronically by now
  • cooling is integrated really well. Literally just hook up coolant hoses and you can trust they'll be cooled efficiently.
  • Power density is huge, basically can ignore voltage sag and just slag them for amps as long as you want, as long as they stay cool
  • delicious 400v architecture
  • not that expensive since everyone wants tesla modules instead
  • pretty safe, with breaks every 72 volts that are fused

cons:
  • energy density is poor. For the same footprint you can get more kWh with other cells
  • even if their footprint is more of a log, they're kinda tall and you can't split them apart beyond a certain point
  • Tricky to wire together in parallel, which you pretty much HAVE To do for any kind of reasonable range
  • The standard charger is nowhere near sufficient and wiring in level 3 fast charging is still an unknown as far as i know
  • Supplies dwindling, there's lots of teslas rolling around but the Volt is getting discontinued

the big one i like is the easy cooling, sounds like if i wanted to use bolt/audi e tron modules i'd have to get some cooling plates custom machined and design the battery box with those cooling plates in mind, lots of unnecessary fab work.
 

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<subscribing for interest>

Always curious about other options. It'll be interesting to see what, if anything, the old heads contribute.
 

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No they are terrible - you should send them all to ME for safe disposal

Seriously they are excellent - they CAN be paralleled very easily

The only problem is the shape - not the T - the cross section they are a bit tall

As far as energy density is concerned if you just use the modules you can save a lot of weight
 

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Discussion Starter #4 (Edited)
As far as energy density is concerned if you just use the modules you can save a lot of weight
hmm, what do you mean by "just the modules"? as in, the individual blades with the bus bars removed?

also more general question: i know with the first gen volt batteries, you can "unlock" more capacity just from software, can you do the same with the second gens? supposedly it's a 14khw usable pack with an actual 18.4khw capacity, i was planning to stick two of those together for a cool 36khw
 

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I kept the modules as is and binned the armour plated base plate - I took the mounting parts off - hundreds of spot welds to drill out

I'm just using the modules so software does not come into it
 

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I'll emphasize one of your pros: cost. Tesla modules are what, twice as expensive per kwh? But they do seem to be coming down slowly, so that advantage is going away.
 

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Discussion Starter #7
I kept the modules as is and binned the armour plated base plate - I took the mounting parts off - hundreds of spot welds to drill out

I'm just using the modules so software does not come into it
what do you do for a BMS, use the one that's on the batteries already and just let them "do their thing", only hooking up your high voltage lines to your motor? what about data lines from the battery to the controller, if any?
 

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Discussion Starter #8
I'll emphasize one of your pros: cost. Tesla modules are what, twice as expensive per kwh? But they do seem to be coming down slowly, so that advantage is going away.
i may be looking in the wrong places but i was seeing ~3.5 grand for a 2016+ volt pack in good condition, at 18 kwh after unlocking, that's $194 per kwh

https://www.evwest.com/catalog/product_info.php?products_id=463&osCsid=qvo87olj969711mtssim4akef5
ev west has model s modules for $1580 per 5.3khw, so $298 per kwh

so, 65% more, not great.

i wonder if there are less expensive Volt battery sources, where i could get packs for 3 grand or below?
 

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Try Car-part.com
I paid $1800 for my volt battery

As far as BMS's are concerned - people who are smarter than me can get the factory BMS to work

I'm skeptical about aftermarket BMS's - from reading people's experience they appear to cause more problems than they solve

I'm using a
http://www.evdl.org/pages/battbridge.html

To detect a cell failure and about twice a year I disassemble enough of my car to check the individual cells
So far so good
And I'm CRUEL to my cells - 1200 amps!

IMHO a BMS will NOT keep your battery working all it will do is tell you if a cell has died so that you can avoid overcharging the others

And my Batt bridge will do that - and it's simple enough that I can understand it

https://www.diyelectriccar.com/foru...dubious-device-44370p15.html?highlight=duncan
 

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Discussion Starter #10
unfortunately my car-part results don't look as rosy out here in california :(

2018 Battery $4005 LKQ-Keystone- Stockton USA-CA(Stockton)
2018 Battery $3805 LKQ-Keystone- Stockton USA-CA(Stockton)
2016 Battery $3605 LKQ-Keystone- Stockton USA-CA(Stockton)
2018 Battery $3245 LKQ-Keystone- Central California USA-CA(Bakersfield)
2016 Battery $3205 LKQ-Keystone- Adelanto USA-CA(Adelanto)
2017 Battery $3500 Basic Auto Parts USA-CA(Los-Angeles)
2016 Battery $2900 Basic Auto Parts USA-CA(Los-Angeles)
2017 Battery $3250.43 All Auto Parts Co. -- Gold Seal USA-CA(Fontana)
big yikes

although if i go for 2012-2016 modules instead it's quite a bit cheaper.

2011 $2500 Nu-Way Auto Dismantling USA-CA(Wilmington)
2011 $2000 American Dismantling Inc. USA-CA(Fontana)
2012 $2000 American Dismantling Inc. USA-CA(Fontana)
2012 $2000 American Dismantling Inc. USA-CA(Fontana)
2012 $2000 American Dismantling Inc. USA-CA(Fontana)
2012 $2000 American Dismantling Inc. USA-CA(Fontana)
2012 $2000 American Dismantling Inc. USA-CA(Fontana)
2012 $2000 American Dismantling Inc. USA-CA(Fontana)

2014 $2285 LKQ-Keystone- Stockton USA-CA(Stockton)
2014 $2285 LKQ-Keystone- Rancho Cordova USA-CA(Rancho-Cordova)
2015 $2405 LKQ-Keystone- Northern California USA-CA(Redding)
2013 $2000 Hybrid Auto Parts USA-CA(Sun-Valley)
2013 $Call Anaheim Auto Wrecking USA-CA(Wilmington)
2013 $1100 American Auto Recycling USA-AZ(Gilbert)
2014 $2350 Spalding Auto Parts USA-WA(Spokane)
2014 $2250 Spalding Auto Parts USA-WA(Spokane)
kinda surprised at the big price delta here
it's segmenting 2012s from 2013s-2014s for some reason though, even though i assume they're interchangeable
 

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Yup, I bought a couple of 1st gen packs for $2k a piece and love them. I don't think there's a big difference with the 2nd gen. Certainly not anything that justifies greater than 50% premium.
 

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The biggest difference appears to be the capacity increase, with a mass decrease. Whether that is worth 50% more is another matter.

https://media.gm.com/content/dam/Media/microsites/product/Volt_2016/doc/VOLT_BATTERY.pdf
Your link formatting is messed up so clicking the link directly doesn't work.

To summarize,
- Pack capacity went from 16.0-17.1 to 18.4 kwh (Gen 1 had a steady increase over the 2011 to 2015 model years) or a 9% - 15% increase Gen 1 to Gen 2
- Pack mass went from 196 kg to 183 kg (unclear how much of that is the pack case versus the cell modules themselves)
- Discharge power went from 110kw to 120kw.

Another factor that weighs into using the Gen 1 vs Gen 2 packs is that the modules in the Gen 1 are 6s and 12s (7 12s and 2 6s) and the Gen 2 are 12s and 16s (4 12s and 3 16s). This could make a difference if you are shooting for a particular voltage or have difficulty integrating larger modules.
 

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Your link formatting is messed up so clicking the link directly doesn't work.
Sorry - usually I check links, but didn't this time. It's fixed now.

Another factor that weighs into using the Gen 1 vs Gen 2 packs is that the modules in the Gen 1 are 6s and 12s (7 12s and 2 6s) and the Gen 2 are 12s and 16s (4 12s and 3 16s). This could make a difference if you are shooting for a particular voltage or have difficulty integrating larger modules.
Yes, they're configured differently, so some of the second generation are larger and there are fewer of them (only seven modules instead of nine).
 

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I have a 2012 Volt battery that I'm putting in my 1981 Delorean (VIN 6673). The T-shape has 30+24 = 54x3p cells at the front and 24+18 = 42x3p cells at the back for a total of 96s3p giving a nominal 355 VDC.


If I move the front 30s3p cells to where the gas tank used to be in the Delorean's frunk, the remaining 66x3p cells at the back fit neatly where the Delorean's PRV V6 engine used to go.


There's an interesting connector between the 30sx3p and 24sx3p modules at the front. It consists of a male and female pair.


What I'd love to buy if anyone has one is that pair, so I can turn it into a six-foot cable between the three modules aft of the cabin and the one module in the frunk.


Does anyone have one that's left over after dismantling their Gen1 Volt battery?
 

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Here's a link to a picture of the connector I'm looking for.
http://clim8.stanford.edu/Gen1Connector.jpg
Actually what I need is everything that connects the rear three modules (total of 66sx3p) to the front one (30sx3p). I should probably separate them physically so as to make clearer what's needed to link them back together electrically. The plumbing part for cooling is clear.


Talking of plumbing, I'm looking for an electrically driven coolant pump suitable for this 96sx3p battery. The Bolt's pump might do; any other suggestions?
 

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That's not a "connector" that is a current sensor - the current goes through the flat conductor

The power electrical connection is all though the simple flat conductors bolted at each end
 

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Thanks, Duncan. I knew it wasn't power, but I was thinking it might be something the modules' BMS's wanted. I'm guessing that each module operates its own BMS independently of the other three modules; if so then I should be able to use the whole 355 volts without any external management of those four BMS units (made by LG Chem?).


However I do want to maintain the battery temperature in the vicinity of 70 F (22 C) which I gather is what GM recommends for optimum performance. So access to the temperature readouts would be great. If it's just one readout per module I should be able to figure that out myself and run the four or whatever wires. What I didn't want to have to deal with was 96 wires, one for each 3p cell block.


Current plan for charging is to do it very slowly for the time being, with no regenerative braking. When I understand the temperature issues better I'll speed up charging. But I may also build a 0.1 or 0.2 megafarad KERS to handle regen, in order not to dump too much energy into the battery all at once. Still in the very preliminary thinking stage.
 

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You are being a bit tender on your battery

I draw 1200 amps from mine - admittedly only for a couple of seconds

As far as cooling flow is concerned I just got a small 12v water pump - you don't need that much flow - IMHO the main thing that the coolant is doing is ensuring that all of the cells are the same temperature
 
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