# Should I buy this Chevy Volt pack?



## Markijohn (Feb 7, 2014)

So I found a pack, we agreed on a price (plus shipping), but they called me to say the pack was damaged. How bad does this look? Do you think the front module could still be ok? Would you think the others would have been affected by the damaged cells in that first module assuming they shorted our something? 

I assume no short since there are no signs of fire...

How much is a good price if we assume the front module is bad? 

Any advice is appreciated!


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## onegreenev (May 18, 2012)

I guess it depends on what they are asking for the pack.


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## Markijohn (Feb 7, 2014)

I agree, what is a good price? We haven't negotiated a new price yet. Shipping will be $200...


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## piotrsko (Dec 9, 2007)

front of pack has the controls, comm boards,manifolds, and relays. battery stuff is about 6-8 inches further back. top of case has more comm, bms boards for at least 4 inches, case is really beefy and kinda empty around the edges, worst possible scenerio I can think of is losing a couple of cell sets on the first string. Junkyard types have no idea of what they are looking at, its just a magic battery box to them. Mine was low miles 2 years old and 2200 with 200 shipping. see if they will go for 1500. might want to hurry, the off grid people know about these also.

pictures would be cool (nevermind) first string batteries look ok to me. cooling manifold is gonna leak make sure that you get a guarantee that it has a charge of at least 270 volts which you cant get to without total disassembly. 
btw: i yanked all the front stuff out.


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## Markijohn (Feb 7, 2014)

piotrsko said:


> front of pack has the controls, comm boards,manifolds, and relays. battery stuff is about 6-8 inches further back. top of case has more comm, bms boards for at least 4 inches, case is really beefy and kinda empty around the edges, worst possible scenerio I can think of is losing a couple of cell sets on the first string. Junkyard types have no idea of what they are looking at, its just a magic battery box to them. Mine was low miles 2 years old and 2200 with 200 shipping. see if they will go for 1500. might want to hurry, the off grid people know about these also.
> 
> pictures would be cool (nevermind) first string batteries look ok to me. cooling manifold is gonna leak make sure that you get a guarantee that it has a charge of at least 270 volts which you cant get to without total disassembly.
> btw: i yanked all the front stuff out.


Thanks for the input. I'm waiting for a call back from them today to negotiate the new price. I'll let you all know how it goes. Worse case, if the front modules are shot for one reason or another, I might have some blocks for sale as I really need a complete pack.


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## Markijohn (Feb 7, 2014)

Small update: Pack is shipping today, should receive it Wed. Keeping my fingers crossed that all the cells are good. If so, then I got this pack at a great price...


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## Markijohn (Feb 7, 2014)

Battery pack received today! Lots of damage in the front, but all the module voltages seem to check out. See images.


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## piotrsko (Dec 9, 2007)

What were voltages of modules??? 120 module looks like it is going to leak if you go water cooled.

Way to go, hope you got a deal on it.


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## Markijohn (Feb 7, 2014)

piotrsko said:


> What were voltages of modules??? 120 module looks like it is going to leak if you go water cooled.
> 
> Way to go, hope you got a deal on it.


Total voltage was above 370V. I have it written down at home on what everything was. I think it was 96.2, 96.2, 69.7, 116.8. This would be 378V total, so that's probably right. 

They had no idea what they wanted for the pack since it was damaged, so they asked what I was willing to pay. I should have shot lower, I'm pretty sure they would have taken just about anything I offered, but at $500, I'm very happy! Though, I did also have to pay full shipping which was $325, so I'm into this pack for $825. Which is an amazing deal I think!

And yes, I don't believe I'll be able to run cooling through those shifted cells without completely taking them apart and restacking, assuming the plastic isn't warped beyond repair. However, I did analysis on A123 pouch batteries about 2 years ago in a sealed pack we designed, and that analysis proved we didn't need to cool it, passive cooling was good enough. My pack will not be sealed, so it will have plenty of ambient air to air cool the pack.


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## piotrsko (Dec 9, 2007)

They would probably air cool using existing heat exchanger plates and you could afford leakage. Thermistors buried in each module for just that purpose. Liberal use of sealer should mitigate leaks. Sorry, I am enamored with chevy liquid cooling and massive overkill engineering.

Smoking deal is an understatement. Stole is closer. I'm jealous. Voltages are high enough to believe you have no bad cells since about 388 is the bms voltage according to chevy.

Be safe. These packs plasma 10 mm. Wrenches faster than my FLA pack did a craftsman 1/2 combo. Nice bright flash, EMT son got pissedoffdude on me.


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## Markijohn (Feb 7, 2014)

piotrsko said:


> Smoking deal is an understatement. Stole is closer.


Yes, that's probably true...


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## Markijohn (Feb 7, 2014)

Another small update... 

So part of the agreement initially was for them to sell me the pack and include the MSD. When I received the pack, they forgot to send the MSD. No big deal, I just called and they agreed to ship it to me. I also decided to ask about the Volt APM (the DC-DC converter). The sales rep said he would check on it and let me know. 

About 2 hours later he texts me pictures of the MSD and APM to ensure they were what I was looking for, I said "Yup, that's them", he replied "I'll get them to UPS today".

No talk of additional $ for the APM. APM showed up today FREE OF CHARGE 
So not only did I get a great deal on the pack, I also got a free APM. I really hope the rest of this build is this easy/cheap!


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## halestorm (Apr 28, 2009)

I suppose I should know this, but what's an MSD? (and what does APM stand for?)


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## Markijohn (Feb 7, 2014)

halestorm said:


> I suppose I should know this, but what's an MSD? (and what does APM stand for?)


MSD - Manual Service Disconnect
APM - Auxiliary Power Module


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## piotrsko (Dec 9, 2007)

(>> In best daffy duck sotto voce: <<) You're despicable....{wiping spittle off}

Mine had the msd. What are you going to do with the apm? Why not get the battery controller also.


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## Markijohn (Feb 7, 2014)

piotrsko said:


> (>> In best daffy duck sotto voce: <<) You're despicable....{wiping spittle off}
> 
> Mine had the msd. What are you going to do with the apm? Why not get the battery controller also.


The APM will be my DC-DC converter. I plan to use the pack in its stock configuration and full voltage range, meaning upwards of 400V peak. Most DC-DC converters I can find only go up to 370VDC and anything that'll do over 400 are expensive. This APM will operate in my desired voltage ranges and I got it for free, so it's a win-win. 

I already know how to make this thing work. I have the CAN messages it needs to wake up. I just now need to build up a CAN controller of some sort. 

I did not get the battery controller because I didn't figure I'd ever be able to get it to work, plus most of the electronics on the front were smashed. I assumed I would never get around to messing with it, so why bother trying to explain to the junk yard guys where and what it was I needed. 

I contacted my GM contact, he said they aren't releasing any CAN information, so tapping into the BMS controller would have to be a complete hack of the system.


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