# cooling Chevy Volt batteries



## halestorm (Apr 28, 2009)

I'm wondering what kind of pumps people are using to cool the Chevy Volt batteries. Specifically what kind of flow rate & head pressure you are using successfully.

Also, what temperature are you regulating at?

Thanks,


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## halestorm (Apr 28, 2009)

Alternatively, if anyone knows the pump specs for the original Chevy Volt, that could be useful as well.

I want to make sure I purchase an adequately sized pump.


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## axex12 (May 26, 2015)

halestorm said:


> Alternatively, if anyone knows the pump specs for the original Chevy Volt, that could be useful as well.
> 
> I want to make sure I purchase an adequately sized pump.


Just recently bought a full volt pack, Its now in shipment. I was thinking 1/2 HP aquarium or pool pump should be good enough? 
BTW are you using BMS?


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## halestorm (Apr 28, 2009)

No one seems to know the original specs of the Chevy Volt pump but I've received two private messages from people. One is using a pump which is rated at 20ft head, 8.7psi, 24L/min. The other is using a pump which is rated at 4 gpm @ 10psi. There's no telling if these pumps are just adequate or overkill. I'm probably going to buy the PMP-500 from Koolance (along with a radiator and pump/fan controller), which is rated at 24.6ft head, 4.2 gpm (16L/min). If I knew I could get away with it, I would rather buy the PMP-450 since by Koolance's own admission it is more reliable than the 500, but it has only half the head pressure.

p.s. Yes, I'm using the Elithion Pro BMS.


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## rwaudio (May 22, 2008)

I'm using a couple of different brand versions of the 450 that you mention, in my Porsche 944, it's a very popular pump for good reason. One runs a loop through the DMOC 645 and the other through the Siemens motor. They surprisingly high flow at max (variable version). Now head pressure is the height you want to pump this water, I'm guessing you don't have more than a foot or two of elevation change in your loop? If that's the case I'd use reliability and flow over head pressure to determine the better choice.

I have a series parallel arrangement of the cooling path in my configuration which would add slightly more restriction (I'm guessing) to the stock configuration of a completely parallel cooling loop as found in a stock volt pack.
Flow seems pretty good but I don't have long term use on it yet.


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## Duncan (Dec 8, 2008)

Hi
Pump requirements
Do you know how much heat you need to reject?

Lets say its 4Kw (5hp) 
4.18 Joules will lift 1 gram of water by 1 degreeC
so 4kw will lift 1 Kg (1 liter) of water by 1 degree each second

So a flow of 1 liter per second will reject 4Kw with a temperature rise of 1 degree

1 degree is small - you can probably get away with 10 degrees
So you need 1/10th liter/second
or 6 liters per minute

If it was mine I would arrange a flow test
Just stick a decent sized container on a hose above the car and see how long it takes to empty flowing through your pack

10m of height = 1 Bar or 14psi


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## halestorm (Apr 28, 2009)

rwaudio said:


> I'm using a couple of different brand versions of the 450 that you mention,


Your private message was one of those I mentioned above. You said you were using the surplus Azure pump from EVTV. Maybe I've got the wrong pump but I looked at their page and they are selling the Pierburg CWA 50 which they claim is from the Azure Connect. EVTV's page says 30lpm, 20ft head, 8.7psi.

The PMP-450 on the other hand is rated at 15lpm, 12.8 ft head (which equates to ~ 5.5 psi for water).



rwaudio said:


> Now head pressure is the height you want to pump this water, I'm guessing you don't have more than a foot or two of elevation change in your loop? If that's the case I'd use reliability and flow over head pressure to determine the better choice.


True, I haven't much height, but I'm worried about the constrictions in the system. I have only a little more than one stock Volt pack (stock pack plus two extra modules) but I'm going to add a radiator. Most people seems are worried about warming their batteries but for me in Southern California I'm worried about heat. I don't know how much pressure I need to get through 1/2 the pack (in front of the car), 1/2 inch hose, the other half of the pack (rear of car), the radiator, then up the ~ 1-2 ft to the reservoir.


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## piotrsko (Dec 9, 2007)

If you are concerned about friction losses, go to 3/4 I'd instead of 1/2. All the Volt hoses look to be 1 inch inside the pack, and 5/8 pipe outside.

I live in reno and it was 103 the day you started this thread. When I got home from work after 7 kWh consumption in 20 minutes, the 5 gallon tank was 120 degrees, no radiator. I did catch most of the lights green, and the a$$ in the Honda stayed 2 cars back. I have a 3% hill on a 1/2 mile on freeway ramp where I am pulling about 400 battery amps for a minute or so and another hill where I pull 300 amps for another minute. If you aren't keeping up with traffic it gets ugly here.

Unless the Volt pump is pushing some huge pressures, 4 -5 gpm sounds ok because the pack doesn't seem to get that hot.


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## rwaudio (May 22, 2008)

halestorm said:


> Your private message was one of those I mentioned above. You said you were using the surplus Azure pump from EVTV. Maybe I've got the wrong pump but I looked at their page and they are selling the Pierburg CWA 50 which they claim is from the Azure Connect. EVTV's page says 30lpm, 20ft head, 8.7psi.
> 
> The PMP-450 on the other hand is rated at 15lpm, 12.8 ft head (which equates to ~ 5.5 psi for water).
> 
> ...


Sorry for the confusion I've built two cars.
The volt packs are in the car using the Pierburg pump, however I have two pumps similar to the PMP-450 in my other car. (for inverter/motor cooling, that car has CALB CA's) and based on flow one pump would have been plenty if I wanted to put the motor/inverter in series in the loop, however they use the same radiator/reservoir but have independent loops each with it's own pump so that I can increase the flow rate through the motor which generates more heat than the inverter.


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## halestorm (Apr 28, 2009)

piotrsko & rwaudio, what kind of cooling hose are you running, type and size?


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## bigmotherwhale (Apr 15, 2011)

these are very reliable, quiet and efficient pumps, 

http://www.swiftech.com/mcp655.aspx#tab2

however you might want to consider using a temperature controller and a pump with a pwm input.

i see you were already considering a pc water cooling pump - good plan, but it would get one with 1/2 inch outputs


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## halestorm (Apr 28, 2009)

That pump looks just like the one I've been looking at,

http://koolance.com/pmp-450-pump-id-13mm-1-2in

I wouldn't be surprised if they were identical, rebranded; not only do they have all of the same specs but they just look the same.

I'm curious what people are using for hoses. The Chevy batteries have a 3/4'' barb; the pump has a 1/2'' barb. I'd like to run 1/2'' ID hose, in part for cost but mostly for space constraint -- I have to fit two of these hoses plus a pair of 2 ga welding cables in the old Porsche 914 heater duct.

PVC tubing like this doesn't seem super-durable to possible bits kicked up from the road (parts of the hose will be exposed to the undercarriage).

Here are some other things I've been looking at, each 1/2'' ID:

Fuel line hose

EPDM Rubber Spray Hose

air hose, mcmaster-carr item 5304K26

high-pressure PVC tubing, mcmaster-carr item 52375K14

automotive heater hose like this
or this
or this

push-lock hose like this
or this


So many choices! I want to keep the price close to $1/ft since I need 50 ft of it.


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## TooQik (May 4, 2013)

halestorm said:


> That pump looks just like the one I've been looking at,
> 
> http://koolance.com/pmp-450-pump-id-13mm-1-2in
> 
> I wouldn't be surprised if they were identical, rebranded; not only do they have all of the same specs but they just look the same.


You are correct, both pumps are rebranded Laing D5 pumps.


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## bigmotherwhale (Apr 15, 2011)

it doesnt really matter what hose you use i used washing machine hose on my PC water cooling rig as it was rated to 90 degrees C and free, it didnt seem adversely affected by the coolant.

the only thing i would say is use stainless steel springs on the inside at sharp bends or at crush points to prevent the hose from blocking.

i would also get a water cooling flow sensor that can be linked up to an alarm so if the pump is on and there is no flow it will alert you to a potential blockage or pump failure air lock etc...


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## piotrsko (Dec 9, 2007)

I get all my fittings/adapters at home despot. 5/8 heater hose because I had a roll, but rubber garden hose would be ok too since the coolant does not get that hot and worse case your at 20 ish psi. For long straight runs you could use that new plastic PEX stuff in red or blue. 

For my soliton cooling I used polypropylene 1/4 drip sprinkler line. Don't know why you couldn't use that on the mains in 3/4 size. Cheap, flexes, has fittings and adapters, deals with Sun heated water.

It isn't like the coolant gets all that hot or is all that aggressive.


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