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This issue might have been discussed on a thread somewhere but it may be a common enough issue that it should have its own thread.

The issue is a compatibility problem between at least some Bolt EVs and the liquid-cooled cables being used on the new high-power chargers being put in primarily by Electrify America (although the problem is not specific to EA). The problem can cause a failure to initiate a charge and could leave someone stranded if they don’t have enough battery range left to make it to an older-style 50 kW charger.

The good news is that this issue has an easy workaround.

I wrote an article recently about this and it embeds a YouTube video created independently by Eric Way that demonstrates the problem and the workaround.

https://electricrevs.com/2018/12/19/some-drivers-struggle-to-use-new-liquid-cooled-charging-cables/
 

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So, hold up the heavy handle until charging starts?

Video

 

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Discussion Starter #3
So, hold up the heavy handle until charging?
Yes. It’s an easy workaround. Just place a hand under the cable leading to the connection with the car to make sure it is evenly inserted and not being pulled down at an angle.

You don’t really need to bother with this unless your initial attempt to charge fails. The problem may or may not happen depending upon how the car is positioned relative to the charger dispenser and cable and thus how much slack there is and at what angle the cable pulls over to the vehicle inlet.

It isn’t clear yet whether this is a problem on other cars also or just the inlet design of the Bolt EV. Even at the same location, some Bolt EVs may have the problem while others do not even though GM says all Bolt EVs have the same CCS charge inlet part design.
 

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Wow, liquid-cooled electrical cables. That's a new one on me. I just hope the liquid is non-conductive.
 

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I dunno, I'd think doing something like Eric makes sense, ie putting something to prop up the handle, because an imperfect connection, while it may charge, could give off excessive amounts of heat.
Yes. It’s an easy workaround. Just place a hand under the cable leading to the connection with the car to make sure it is evenly inserted and not being pulled down at an angle.

You don’t really need to bother with this unless your initial attempt to charge fails. The problem may or may not happen depending upon how the car is positioned relative to the charger dispenser and cable and thus how much slack there is and at what angle the cable pulls over to the vehicle inlet.

It isn’t clear yet whether this is a problem on other cars also or just the inlet design of the Bolt EV. Even at the same location, some Bolt EVs may have the problem while others do not even though GM says all Bolt EVs have the same CCS charge inlet part design.
 

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Seems to me the cost of the equipment needed to charge a BEV using current rates high enough to require liquid cooling must be very expensive.

Should a BEV owner who stops along the route to recharge at such a fast-charging station expect to pay at least five to ten times more than they would pay to put the same amount of kWh into a battery using L2 charging equipment?
 

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I dunno, I'd think doing something like Eric makes sense, ie putting something to prop up the handle, because an imperfect connection, while it may charge, could give off excessive amounts of heat.
As far as I know, the cable connection is fine once the motorized clamp on the vehicle inlet is successful in grabbing onto the CCS connector. I think there is a temperature sensor in the connector and the vehicle inlet so excessive temperatures would be detected and cause chargingvto slow or end. Eric may have said something about his charge session eventually ending prematurely but it’s not at all clear to me that is was caused by excessive temperature issues due to a poor connection. I personally have not seen any excessive heat on connections that I successfully started by using the workaround technique of supporting the cable for the first few seconds of the session.
 

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Seems an odd solution, to say the very least. You have a cable which is several wire sizes too small for the job, so it drops voltage and overheats. Rather than replacing the undersized wire with the correct size, you attempt to liquid cool it. It's still too small, it still drops voltage and it still gets hot, so cooling it is the 'solution'??

I'm sure this makes sense to somebody . . . . but I can't imagine why

Don
 

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Yah, you think it would be cheaper to run a thicker wire than build and maintain a water cooled cable unless there is some underlying thing that isn't self evident.
 

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Seems to me the cost of the equipment needed to charge a BEV using current rates high enough to require liquid cooling must be very expensive.

Should a BEV owner who stops along the route to recharge at such a fast-charging station expect to pay at least five to ten times more than they would pay to put the same amount of kWh into a battery using L2 charging equipment?
Not for a commercial station.

Same accounting overheads, some similar labor, but served kWh/h are much greater, and less opportunity cost loss due to occupancy, which reduces the cost of money.
 

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Seems an odd solution, to say the very least. You have a cable which is several wire sizes too small for the job, so it drops voltage and overheats. Rather than replacing the undersized wire with the correct size, you attempt to liquid cool it.
I suspect that you are woefully underestimating the thickness of the two conductors that would be required carry 350A.
 

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Tesla had a prototype of liquid cooled cables at the Mountain View Supercharger for a while. (The MV Supercharger is located in the parking lot behind the Computer History Museum. Just a couple blocks from Google HQ.). They installed the cables just prior to the 2016 (I think) TSLA Shareholders meeting - which I attended. There were engineers on site to answer questions. The cables were about the same thickness as the ones in the HPWC - much easier to handle than the normal SC cables. Cooling gear in the base of each pedestal. At some point Tesla swapped them out and went back to the regular cables. I have no idea why.
 

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Wow, liquid-cooled electrical cables. That's a new one on me. I just hope the liquid is non-conductive.
Actually, this is a thing, and underwater cables are rated for a current carrying capacity based on being underwater and the heat being more efficiently rejected to the water from the cable. Mackinac Island in Michigan found this out in the summer of 2000, when the lake level had dropped enough that the cable feeding the island were out of the water for the last bit of the run and overheated, resulting in failure of 5 of the 7 cables feeding the island.

So they are using the dielectric liquid in the cable to cool the wiring, allowing the conductors to be smaller. The weight is probably similar or less than a comparable larger diameter cable. I suspect the liquid cooled cable is much more flexible.
 
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