JeffN
Posts: 141
Joined: Fri Apr 01, 2016 7:32 am

Re: EVgo DC chargers were horrible up until the beginning of 2018. They're still not perfect, but improvement is being m

Sat Jan 26, 2019 11:02 pm

Pigwich wrote:This covers everything.
https://en.wikipedia.org/wiki/Combined_Charging_System

CCS1 does 200 amps, CCS2 does 500 amps, how they balance the voltage out in that equation will be entirely up to the power supply designer, they'll either max out at a number of amps, or a max grand total power.

Also, doesn't matter, the bus bars in the Bolt's battery won't handle any more amperage by the looks of them, but maybe one day they'll have 800V Bolts? Just a matter of a new battery, new air conditioner, new inverter, new charger, new motor, new heater, new DC-DC converter........

The bus bars in the Bolt battery already handle 400A at least for awhile since the pack output is rated for a peak of 160 kW (400A @ 400V or something like that).

I think the limitation on the car’s DC charging rate lies elsewhere.

JeffN
Posts: 141
Joined: Fri Apr 01, 2016 7:32 am

Re: EVgo DC chargers were horrible up until the beginning of 2018. They're still not perfect, but improvement is being m

Sat Jan 26, 2019 11:15 pm

SparkE wrote:For example, the last one I really paid attention to was the ChargePoint "Express 250", it is listed as "max 156A, 200–1,000V DC" . It turns out that the max power is 62.5 kW, not 156kW (156A x 1000V) - which works out to 156A around 400V (which is a reasonable V for today's cars).

That unit is the least powerful of ChargePoint’s set of new higher-powered charging equipment. Since it is only 156A it uses conventional charging cables. They have variations using the same dispenser unit but wiring it up either with another one nearby or with a charger cabinet that has additional charging circuits.

The "proto" ABB "150 kW" DCFC in Fremont, CA will supposedly offer a max of 350A (which I find very hard to believe, as the cables don't seem to be liquid cooled) up to 920V. Realistically, battery packs these days run up to 370-375V (approx), so it's really a "130 kW" unit (and if it can only supply 200A, it's a 75 kW unit).

That old prototype has never been available for public use and is going to be replaced with final production equipment that uses liquid-cooled cables.

Pigwich
Posts: 240
Joined: Tue Jan 03, 2017 2:01 pm
Location: Southern California

Re: EVgo DC chargers were horrible up until the beginning of 2018. They're still not perfect, but improvement is being m

Wed Jan 30, 2019 9:08 pm

The bus bars in the Bolt battery already handle 400A at least for awhile since the pack output is rated for a peak of 160 kW (400A @ 400V or something like that).


Yeah.... true, I would wager that that isn't a "continuous" power rating but probably something a lot closer to a 1 minute rating.

Figure this, a 12 x 3 mm bar of copper, 30 cm long, 0.0001398 ohms, moving 400 amps will dissipate 20 watts of heat. Is that the size of the bus bar in the Bolt? Nope. No idea, and 20 watts doesn't sound like a lot of power, but over a minute its 1200 joules, which in to a quarter pound of copper is a temperature rise of 28C. Non-zero. So my point here is YES, you're right, 400 amps, but keeping that up for any time period is serious business.

I also have to agree with you here - I don't think the size of that bus bar, or ANY bus bar in the system is the limiting factor in how fast the cells will charge, but to be certain, if charging rates go up, way more than the cells themselves will need to change. And these water cooled DCFC cables are a pretty obvious solution too. God....though I shudder to think about every stupid wire needing to have coolant flowing through it. Reliability is going to take a major dump and service will be a nightmare. We just need more restaurants, coffee shops, playgrounds, parks and libraries at DCFC stations. Heaven forbid we stretch our legs every 3 hours.
(´・(oo)・`)

BoltEV
Posts: 225
Joined: Thu Feb 01, 2018 5:58 am

Re: EVgo DC chargers were horrible up until the beginning of 2018. They're still not perfect, but improvement is being m

Wed Jan 30, 2019 11:30 pm

Pigwich wrote:As has been pointed out in another post, EVgo has a policy of turning off their fast chargers after a 30 minute session, regardless of the SOC of the vehicle.

Do you still claim this to be true?

SparkE
Moderator
Posts: 1115
Joined: Sun Sep 11, 2016 5:53 am
Location: SF Bay Area

Re: EVgo DC chargers were horrible up until the beginning of 2018. They're still not perfect, but improvement is being m

Thu Jan 31, 2019 5:27 am

I believe it was true when it was posted (two years ago). Since then, EVgo has introduced new plans, which have time limits of either 45 mins or 60 mins (the 60 min limit is for '$10/mo subscribers", and only from 8pm-6am).

Although a while back, there was a report that if you never contacted EVgo to switch off the "old" plan (pre-march 2018) that you not only got charged the higher old prices, but there was also still a 30-minute limit.

SparkE
Moderator
Posts: 1115
Joined: Sun Sep 11, 2016 5:53 am
Location: SF Bay Area

Re: Do not use EVgo fast chargers. No, seriously. Just don't.

Mon Feb 25, 2019 9:21 pm

ChargePoint in June 2018 wrote:Hi!
We expect all ChargePoint DCFC stations on I-5 to be active by October 2018!
We shared that news in our main thread, however, I am not able to share any further updates at this time. :)

Here's that post here in the forum: viewtopic.php?p=31400#p31400


October 2018 was wildly optimistic , however I-5 is now, finally, fully drivable from the L.A. basin up to the Bay Area, and Sacramento, and beyond what with the latest openings of ChargePoint sites in Coalinga and Gustine.

There are multi-DCFC sites at :

- Coalinga (ChargePoint) - ~100 miles N of Bakersfield

- Gustine / Los Banos (ChargePoint) - ~100 miles N of Coalinga, ~100 miles S of Sacramento

{{ From either Coalinga or Gustine you can head W on CA-152 and fill up at the 6-stall Recargo site in Salinas and on to the Pacific Coast and/or south Bay Area) - or use the EVgo sites Gilroy / Hollister / Watsonville / Salinas }}

If you drive N from Gustine, you can divert to CA-99 around Modesto if needed (multiple EVgo sites along CA-99), but Sac is only ~100 miles from Gustine.

And the new 4-stall (150 & 350 kW) Electrify America site in Dunnigan is about 150 miles N of Gustine on I-5.

Up I-5 (north) there's :

- a multi-stall DCFC site (ChargePoint, 125A, "50 kW") in Red Bluff (~95 mi N of Dunnigan, ~130 mi N of Sacramento)

- single DCFC (ChargePoint, 125A, "50 kW") sites in :
+ Redding (~30 mi N of Red Bluff, ~125 mi N of Dunnigan, ~165 miles from Sacramento)
+ Dunsmuir (~50 mi N of Redding, ~85 mi N of Red Bluff, ~175 mi N of Dunnigan)
+ Mt Shasta (~10 mi N of Dunsmuir, ~60 mi N of Redding, ~95 mi N of Red Bluff, ~185 mi N of Dunnigan)
+ Weed ( ~10 mi N of Mt Shasta, ~20 mi N of Dunsmuir, ~70 mi N of Redding, ~105 mi N of Red Bluff, ~195 mi N of Dunnigan)


And "soon", a multi-stall Electrify America site in Yreka (about 30 miles N of Weed and 25 miles south of OR border).

There are already multi-stall EA sites on I-5 in OR (Grants Pass, Sutherlin, Albany) and Vancouver, WA (just N of Portland OR) as well as *multiple* other vendor DCFC sites in Salem and Portland (EVgo, ChargePoint, independants). And "soon", more multi-stall Electrify America sites in Eugene, Salem, and multiple sites in/around Portland, OR and Olympia and Renton and Redmond and Everett WA, not to mention the other sites already installed around those points.

So, single-company charging is a thing of the past for some of us on the west coast! One can travel N-to-S (and vice-versa) in Calif choosing among the fast chargers one prefers (when available). Heck, travel from San Diego all the way to Canada is now pretty stress-free for Bolt drivers. And the Calif coast is also do-able the full length of US-101 from L.A. basin up to Oregon. Travel to Tahoe and Reno is covered well also.

And travel in Calif is only going to get better once those DAM slow-to-be-installed CEC fast charger sites get installed. (The eastern part of the state, especially the eastern side of the Sierras, is still pretty difficult or impossible.)

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