PPL
Posts: 20
Joined: Mon Oct 20, 2014 9:20 am

6.6kW charging

Wed Nov 05, 2014 12:31 pm

From reading the technical disclosures from Chevy on their upcoming 2016 Volt, it looks like Chevy is committed to keeping 3.3kW charging in all their EVs. They are fixed on the view that for overnight charging, there is little benefit for faster charging.

For the Volt which has RE motor, I probably agree. However, I think Spark EV really should have a 6.6kW charging instead of 3.3kW. W/o DC charging widely available, I find that using Level 2 EVSE at 3.3kW to be hard to justify when I need a very fast recharge. The keyword being fast; 7 hrs. on Level 2 is faster than Level 1 but not against 4 hrs. on Level 2.

Just for my own edification, can someone point me to so information on what/how a 6.6kW charger differs from a 3.3kW charger? Is there any possibility for an after-market upgrade of the on-board 3.3kW charger to a 6.6kW charger?

There were some discussions on the Leaf forum for upgrading the early Leafs chargers but I could not find a definitive answer on what it takes or if it is possible.

Thanks.

TonyWilliams
Posts: 572
Joined: Sun Apr 14, 2013 4:23 pm

Re: 6.6kW charging

Wed Nov 05, 2014 2:55 pm

Guys on the LEAF forum mounted a Brusa 3kW charger under the hood (we actually built a mounting plate in my garage for that).

You could certainly do the same. You'll need to learn the pertinent CAN bus messages that control charging, and be knowledgeable about DEADLY high voltage.
Contrary to many folks here, I do NOT own a LEAF.

cwerdna
Posts: 478
Joined: Sun Nov 03, 2013 12:35 am
Location: SF Bay Area, CA

Re: 6.6kW charging

Wed Nov 05, 2014 10:59 pm

PPL wrote:From reading the technical disclosures from Chevy on their upcoming 2016 Volt, it looks like Chevy is committed to keeping 3.3kW charging in all their EVs. They are fixed on the view that for overnight charging, there is little benefit for faster charging.

For the Volt which has RE motor, I probably agree. However, I think Spark EV really should have a 6.6kW charging instead of 3.3kW. W/o DC charging widely available, I find that using Level 2 EVSE at 3.3kW to be hard to justify when I need a very fast recharge. The keyword being fast; 7 hrs. on Level 2 is faster than Level 1 but not against 4 hrs. on Level 2.
That is really disappointing to hear, even w/the Volt. It really helps to have a higher wattage OBC so that one can pick up more charge within a given amount of time when opportunity charging as well as allowing for quicker turnover of spots (e.g. workplace charging). We have a number of Volts at my work but only 2 or 3 Spark EVs.

I've started sessions for plenty of Volts at my work on our L2 208 Volt Chargepoint EVSEs. They only pull ~3.1 kW from the wall vs. 5.7 to 6.0 kW of my '13 Leaf and ~6.2 kW for the Tesla Model S cars at work. Just recently, my work installed 4 Tesla HPWCs (http://shop.teslamotors.com/products/hi ... -connector). I've not confirmed whether they're each on a 100 amp circuit. If so, that'd allow for 80 amp charging, which would be ~16.64 kW @ 208 volts.

gatedad
Posts: 34
Joined: Thu Sep 12, 2013 8:31 am

Re: 6.6kW charging

Fri Nov 07, 2014 12:40 pm

I know that GM clearly indicated that for the Volt they see no need for QC, and I guess I understand that position. However, for Volt(and ESPECIALLY)for the Spark EV, the 6.6 OBC would be the preferred way to go. After driving a BEV that had 3.3 OBC, and no QC, I quickly learned that it limited my opportunity to use the car as often as I would have liked. If you live in an area where there is little to no QC available, having the ability to add 20 miles in an hour via Level II softens the sting a bit. In my case, I'd take the car to work, with a round trip of 32 miles and come home with a little more than half of a battery(maybe 35-40 miles available---and much less in winter). That was actually fine, until I needed to go somewhere that was 10-15 miles away, and did not have time to charge the car up for several hours at a Level II facility(I used 120V trickle charge at home). Made no sense to drive to a Nissan dealer and sit there for an hour to add only 10 miles additional range. Honestly, I don't know why(other than costs)any manufacturer would release a BEV with less than 6.6 OBC.
Lou

buickanddeere
Posts: 146
Joined: Wed Apr 17, 2013 2:27 pm
Location: East coast of Lake Huron

Re: 6.6kW charging

Sat Nov 08, 2014 10:19 am

I don't see how a 6.6Kw charger is a whole lot more $$$ to install in a Volt or Spark than a 3.3Kw.

PPL
Posts: 20
Joined: Mon Oct 20, 2014 9:20 am

Re: 6.6kW charging

Mon Nov 10, 2014 9:49 am

For a company like GM who claims they track detailed User profiles due to OnStar, I can't understand this 3.3kW charging view. GM always seems to make some strange decisions with Volt/ELR and Spark EV. All 3 forces the owners into some compromises.

As for added cost between 3.3kW vs 6.6kW, I would expect higher cost but at least make that available as an option like the DC FC. Nissan does that on their lowest cost Leaf. I took the DC FC option but the odds of finding SAE combo chargers are not good.

Considering how efficiently the ReGen works in adding backs miles, I wonder why no one has created a electric motor driven DC recharge system. Even if it takes a 240v motor and a few hours to charge, it might be better than trickle charge at Level 1.

buickanddeere
Posts: 146
Joined: Wed Apr 17, 2013 2:27 pm
Location: East coast of Lake Huron

Re: 6.6kW charging

Mon Nov 10, 2014 10:49 am

buickanddeere wrote:I don't see how a 6.6Kw charger is a whole lot more $$$ to install in a Volt or Spark than a 3.3Kw.
Please explain your last paragraph with the 240 charging generator.

PPL
Posts: 20
Joined: Mon Oct 20, 2014 9:20 am

Re: 6.6kW charging

Mon Nov 10, 2014 2:47 pm

Just a wish due to lack of SAE DC charging stations. I got the Spark EV with the optional DC FC and have not been able to find any public chargers that support SAE.

I am sure you noticed that ReGen mode in any EV is quite efficient at adding more miles back. Very noticeable in a long downhill runs. This is due to the ReGen mode using the drive motor as DC generator to directly charge the battery.

Just wondered if it is feasible to get a similar DC electric generator that is geared to an 240V electric motor and use it to charge via the SAE DC charging terminals. Probably too noisy even if it is feasible.

emv
Posts: 193
Joined: Sun Mar 02, 2014 10:47 pm
Location: PDX

Re: 6.6kW charging

Tue Nov 11, 2014 11:43 am

buickanddeere wrote:I don't see how a 6.6Kw charger is a whole lot more $$$ to install in a Volt or Spark than a 3.3Kw.
NEVER underestimate the bean counters at GM. :!:
2014 Spark, 2005 Prius. When we take the Prius we say we're taking the gas hog.

emv
Posts: 193
Joined: Sun Mar 02, 2014 10:47 pm
Location: PDX

Re: 6.6kW charging

Tue Nov 11, 2014 12:02 pm

PPL wrote:Just a wish due to lack of SAE DC charging stations. I got the Spark EV with the optional DC FC and have not been able to find any public chargers that support SAE.

I am sure you noticed that ReGen mode in any EV is quite efficient at adding more miles back. Very noticeable in a long downhill runs. This is due to the ReGen mode using the drive motor as DC generator to directly charge the battery.

Just wondered if it is feasible to get a similar DC electric generator that is geared to an 240V electric motor and use it to charge via the SAE DC charging terminals. Probably too noisy even if it is feasible.
What you are talking about was common in the past and was called a motor-generator. Most often used to step-up or step-down from one DC voltage to another. You just don't see them anymore as they are expensive, noisy, and inefficient. You would also have to communicate with the car but that shouldn't be too difficult perhaps on the order of making a Chademo to SAE Combo converter ;)

Without a lot of work and a lot of money we're stuck at 3.3kw.
2014 Spark, 2005 Prius. When we take the Prius we say we're taking the gas hog.

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