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Discussion Starter #1
In addition to a somewhat weak L2 apparently the CCS socket was and is a cheap 150 amp version. Someone can come here with proof I'm wrong but since this is just a socket I would guess it wouldn't have cost GM much at all for the 200 amp version. Now it makes sense why charging is slower than it has to be GM "bean counting"...
 

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The charge connector, and the wires going from the connector to the battery are rated for 150 amps max. I got this from the Bolt and Volt lead engineer a couple years ago when I met him at a EVGo charger near Chicago. He explained that cell chemistry would be fine at higher charging speed, but that the charge connector and interconnecting wiring were not rated for more than 150 amps.

Keith
 

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Yeah, I don't think Eric really claimed to be revealing this so much as finding it out for himself and his thoughts on it.

When the Bolt came out there wasn't really any public >150 amp chargers out there. Even now they are almost exclusively the domain of Electrify America. So it isn't insane that GM hasn't gone to the trouble of upgrading it. Not to say they shouldn't, just that I get not going to the trouble of it yet.

As for L2, somewhat similarly I don't know how much benefit there would be to upgrading it from 32 amps. How many would actually take advantage of faster charging? We already have people advocating that L1 is enough (I disagree, but that's another discussion), would it really be worth the expense to install an 80 amp charger all would pay for but few would take advantage of? Even those going L2 might explore the cost to install a 100 amp sub panel and choose instead to go with 32 or 40 amps.

EDIT: Typo
 

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Yeah, I don't think Eric really claimed to be revealing this so much as finding it out for himself and his thoughts on it.

When the Bolt came out there wasn't really any public >150 amp chargers out there. Even now they are almost exclusively the domain of Electrify America. So it isn't insane that GM hasn't gone to the trouble of upgrading it. Not to say they shouldn't, just that I get not going to the trouble of it yet.

As for L2, somewhat similarly I don't know how much benefit there would be to upgrading it from 32 amps. How many would actually take advantage of faster charging? We already have people advocating that L1 is enough (I disagree, but that's another discussion), would it really be worth the expense to install an 80 amp charger all would pay for but few would take advantage of? Even those going L2 might explore the cost to install a 100 amp sub panel and choose instead to go with 32 or 40 amps.

EDIT: Typo
While Eric has an interesting idea, I'm pretty sure GM doing any retro fitting is pie in the sky. A third party maybe, but I doubt the market is big enough for even that. I really don't see any changes coming until GM releases their next generation battery.
 

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While Eric has an interesting idea, I'm pretty sure GM doing any retro fitting is pie in the sky. A third party maybe, but I doubt the market is big enough for even that. I really don't see any changes coming until GM releases their next generation battery.
And word on the internet is that the next Bolt will NOT be getting the new battery architecture. So, my next EV may be from GM, but it will not be a Bolt.

Keith
 

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And, as has been pointed out before, changing the socket in the port does not fix the problem unless you replace the wiring from the port to the HPDM, inside the HPDM, and the wiring to the RESS.
 

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In addition to a somewhat weak L2 apparently the CCS socket was and is a cheap 150 amp version. Someone can come here with proof I'm wrong but since this is just a socket I would guess it wouldn't have cost GM much at all for the 200 amp version. Now it makes sense why charging is slower than it has to be GM "bean counting"...
I really don't understand why anyone would be surprised that GM would use components that were appropriate for the design specs of the car.
 

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I really don't understand why anyone would be surprised that GM would use components that were appropriate for the design specs of the car.
Yeah, the "cheap" 150 amp version was designed to exceed any CCS charger on the planet when it was designed... they could have easily designed it to meet the 125 amp or (shudder to think it) 100 amp spec and saved a lot of money over designing the charge port to exceed what was available from the charging infrastructure at the time when they were designing the car.

Keith
 

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Discussion Starter #9
Well I realize it all needs to be made to a cost to come within their budgets. I still would have liked to have OPTIONS for better charging, better HVAC and better seats. I actually don't care too much about these items right now (because my current commute is less than 10 miles round-trip - car is actually opposite of Eric's - very underutilized). I know these items will bother me if I ever manage to make it out of commuting to a job into doing road trips in retirement. I took a few road trips in 2.5 year and those 3 items are weak points on the highways. Good news is GM has lots of room for improvement.
 

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In the same video, he mentions the batteries can't be charged above 1C which is 60kW. It can already charge at 55kW until it steps down. Are we really going to quibble over 60kW vs 55kW and who would pay $1500 for that difference? Seems to me they picked the socket that was compatible with the battery charge rate.

Mike
 

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Well I realize it all needs to be made to a cost to come within their budgets. I still would have liked to have OPTIONS for better charging, better HVAC and better seats. I actually don't care too much about these items right now (because my current commute is less than 10 miles round-trip - car is actually opposite of Eric's - very underutilized). I know these items will bother me if I ever manage to make it out of commuting to a job into doing road trips in retirement. I took a few road trips in 2.5 year and those 3 items are weak points on the highways. Good news is GM has lots of room for improvement.
Besides costing more, increasing the rate of charge increases the weight of the vehicle and since all that copper doesn't contribute to performance or efficiency, both performance and efficiency go down due to the increased weight. Even if money isn't an object, overcoming the performance declines requires increasing the power of the motor and the size of the battery and this decreases the efficiency of the vehicle. There are just trade-offs that must be made.
 

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Besides costing more, increasing the rate of charge increases the weight of the vehicle and since all that copper doesn't contribute to performance or efficiency, both performance and efficiency go down due to the increased weight. Even if money isn't an object, overcoming the performance declines requires increasing the power of the motor and the size of the battery and this decreases the efficiency of the vehicle. There are just trade-offs that must be made.

If the Tesla charge port and interconnecting cableing capable of 250 KW charging speed weighs 10 lbs more than the Bolt I would be shocked, I suspect it is much less of a difference than that.... and 10 lbs is not going to affect your range or performance.

Keith
 

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To double the potential rate of fast charge you would need to at least double the amount of copper in the whole current carrying system that runs from the receptacle to each individual cell. This is probably the largest electrical system in the car and my guess, since we're guessing, is more like 50 pounds and to reduce heating, since merely going up proportional to the rise in current would lead to proportional increase in heat, it could easily be necessary to add even bigger conductors. Since the global market for copper goes up and down due to projected Tesla sales, I think they use a lot of copper.
 

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Well I realize it all needs to be made to a cost to come within their budgets. I still would have liked to have OPTIONS for better charging, better HVAC and better seats.
GM is not Tesla. It's a traditional car manufacturer that builds a vehicle and sells it to you, and aside from warranty claims, safety recalls and parts support that's basically where your relationship ends. Your car can do what it can do, don't expect it to grow new capabilities in the future.

The day may come when Tesla has a big enough effect on the industry that other manufacturers start to adopt it's software upgradability model. But that day is not here yet.
 

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To double the potential rate of fast charge you would need to at least double the amount of copper in the whole current carrying system that runs from the receptacle to each individual cell. This is probably the largest electrical system in the car and my guess, since we're guessing, is more like 50 pounds and to reduce heating, since merely going up proportional to the rise in current would lead to proportional increase in heat, it could easily be necessary to add even bigger conductors. Since the global market for copper goes up and down due to projected Tesla sales, I think they use a lot of copper.
Point 1: To double the current carrying capacity of a wire does NOT require doubling the amount of copper... where did you get that silly notion?

Point 2. Point 1 even if true would be irrelevant. The Bolt can charge at 150 amps, Eric is requesting an increase to 200 amps... not 300 amps... an increase of 33% not 100%

Point 3: The charging cables involved go to the battery quick disconnect on the battery pack. Internal current is carried by buss bars.

Point 4: Even if all of your wild notions were true, 50 lbs of weight gain would be virtually irrelevant in terms of efficiency and performance.

Later,

Keith

PS: No way in **** would I pay for an upgrade, I will just get a different EV with better technology (GM BEV3, Ford Mach E, Rivian, Tesla etc) It is just your reasons for disliking the idea that are silly. If your notions are correct we would all be better off going to cars that could only charge at 24 KW. They would perform so much better because of how much lighter they were! Give me a break.
 

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Discussion Starter #16
GM is not Tesla. It's a traditional car manufacturer that builds a vehicle and sells it to you, and aside from warranty claims, safety recalls and parts support that's basically where your relationship ends. Your car can do what it can do, don't expect it to grow new capabilities in the future.

The day may come when Tesla has a big enough effect on the industry that other manufacturers start to adopt it's software upgradability model. But that day is not here yet.
My counter argument to those points
#1. I recall reading The Bolt actually is a reaction to Tesla. GM fast tracked the program because they were worried about falling behind in EV tech. I recall the article specifically mentioned as a reaction to Tesla.
#2. I also recall there being market research surveys from GM discussed here investigating possible prices for a "cold weather Option package" basically a heat pump. So GM is aware now that at least some people are interested.
#3. Many years before and since Tesla there have been many different versions of the same basic car with various trim levels offering different types of seats, engines etc. Just look at the New Corvette they will probably have 5 different trim levels total! Having a 3rd trim level with things like bigger battery capacity, faster charging, heat pump, upgraded seats and even built in AC power inverter seems easily doable by GM and something they would WANT to do if they can charge more for the same basic product platform! I guess technically EUV will be considered the 3rd version? At the very least it might make the products more competitive / desirable and able to sell with less incentive cash! Thanks to Hertz going bankrupt there is one less big Customer GM can sell to now.
 

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Point 1: To double the current carrying capacity of a wire does NOT require doubling the amount of copper... where did you get that silly notion?
You're right, it doesn't require twice as much copper - in fact it needs quite a bit more than twice as much.

See: Common US Wire Gauges - AWG Gauges vs Current Ratings

The amount of copper needed is the cross-sectional area of the wire times the length of the wire. For example, note that for a single-core wire carrying 154A, you need a cross-section of 26.7 mm² , but if you approximately double the current to 325A you now need a cross-sectional area of 107 mm² , an increase of approximately four-fold.

Even going to just 200A would require 53.5 mm² , which actually is double the amount of copper.

The reason the cross sectional area goes up so rapidly is due to the cooling requirement - heat generated in the surface of the wire is dissipated more readily than heat generated in the core of it - and the thicker the wire the harder it is to dissipate the heat from the core.

This is exactly why high-capacity chargers have actively cooled cables. The Bolt could cut down on the copper requirement by using active cooling on its own internal cables, but that would increase costs too, probably more than for just the extra copper that would otherwise be needed.
 

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My counter argument to those points...
I think I mis-interpreted your original post to suggest you were hoping that GM would provide some sort of upgrade path for existing Bolts, but upon re-reading it I don't think that's what you were saying. I agree that GM could offer factory options for purchase with the car, but I suspect their focus is on the newer generations of EVs that they're working on with their new modular battery platform. I doubt we'll see any significant improvements in future model years of the Bolt unless they decide to come up with a "Gen 2" version that uses the new EV platform.
 

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I posted this in the Charging and Battery area before seeing this thread. Copying here ...

You know, "News Coulomb" used to be the biggest Bolt fan-boy on this site. As a gross over-simplification, the Bolt had virtually no flaws, and Teslas had no real advantage over a Bolt.

The "discussions" that made this most clear were ones that mentioned any limitation / inconvenience of the Bolt when "road tripping" : long trips (>350 miles?). He was adamant that the Bolt's max charging rate (150A, a max of ~55kW for a very short window) was just fine and not a limitation, that the early "step down" spots (around 50% and 70%, to 100A and 60A, respectively) was not a big deal, that there were enough CCS fast chargers for long distance travel, later changed to "EA will have a network equal to Tesla's by 2019, so isn't that big of a deal" (BTW, in 2020 EA does NOT have a network equal to Tesla's 2018 network, either in quantity or quality), and that Teslas didn't really have much of a charging advantage because their "charging curve" tapered down "more quickly" (based on 130 kW going to 60 kW at some battery SoC means that it loses 50% of its charging speed!) - completely ignoring that at 70% SoC a model3 is still charging faster than the max charge rate of a Bolt at any SoC.

Anyhow I now find it amusing that he has recently posted a youtube video where :

(a) he talks up the 2020 Bolt's new gradual taper (a reversal of his earlier point of view). "This {charging curve} gives the 2020 Bolt a massive advantage when charging to higher than 50-60% {over the earlier model Bolts} as you charge to higher states of charge"

(b) GM should change/upgrade the CCS socket on the Bolt, which has a (max) 150A connector, to a 200A socket.

(c) GM should make it possible to get the "2020 charging curve" on the pre-2020 Bolts, instead of the step-down charging profile.

So, now he thinks that the charging "step down" instead of "curve" is important, 150 amps really aren't enough, and the battery should be charged more quickly : at its fastest, around 1C {about 60 kW on pre-2020 Bolts and 66kw on the 2020 and later} and additional power should be available via the CCS plug to run battery and cabin heating / cooling while charging the battery at the highest possible rate for its chemistry. So I guess that it turns out that the Bolt doesn't charge quickly enough, a complete reversal of 2 years of him arguing on this site. I find the whole thing highly amusing. Also amusing is that while he was talking about point (b), he showed video of a charging session at a DCFC that provides a max of 125A, so a 200A socket wouldn't make any difference!

He also pointed out that this would be an optional upgrade for 2017-2019 Bolt owners, which they would have to pay for, generating income for GM dealerships (absolutely true, BTW), and it would "result in a much more capable electric vehicle than you had before". But, but, but ... Coulomb, you used to say that the vehicle was perfect the way it was!

This is the only NC video I have watched all the way through, because (a) a guy recording himself talking to himself, often about himself, in his car isn't that interesting to me, and (2) the parts of his videos that I have watched are 80-90% "blah, blah" and maybe 5-10% actual, useful info. I think that the longest I have watched any of his videos up until now was about 8-10 minutes, and that was because I really wanted to hear about the specific DCFC sites that he was reviewing. The useful info could have been given in about 60 seconds instead of 10 minutes, and at some point I just couldn't take it anymore and had to stop watching.

PS : All cars have their pros and cons - and it often depends on YOUR specific needs / point of view. Pro of the Bolt : availability, and actual price that you pay out-the-door for a vehicle that meets most people's generic needs for an everyday car - or "not super long range" trips (one can find new Bolts around $25-$28k +taxes, often). It really is a very good all-round vehicle. Major cons (for me) : one of the slowest "fast" charge rates, so not a very good choice as a vehicle used often for long range trips, the driver seat (for some people).
 

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Inclined to agree with the above thoughts. Part of the lure of Tesla is the access to the Supercharger network. And they’re actively rolling out v3 Superchargers which support 250 kW sessions independent of the other cabinet (in v2 Superchargers one of the two connectors per cabinet will be faster than the other as they’re linked to a maximum output.)

If DCFC was something that I thought I would be using regularly, it’s hard to justify a Bolt right now.

For reference with v3 at 250kW, a Model 3 charged from 2% to 50% in the blink of an eye.

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