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If I understand correctly, my 2021 Bolt can fast-charge up to 50 kw. The other night I had to use a public station on a long trip and saw that I had a choice of 150kw and 350kw. Other stations offer 50kw and 62.5 kw.

I used the 350kw one, plugged in for 31 minutes and my Bolt's range display went from 81 miles to 164 miles (whoa, that's faster than my Level 2 unit at home!) The cost was around $5 (Electrify Ameri

Q: in regular, practical terms, what do I need to know about choosing 50 vs 62.5 vs 150 vs 350? Should I always choose the highest kw so that it charges as fast as possible?

bolt-charging.jpg

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If I understand correctly, my 2021 Bolt can fast-charge up to 50 kw. The other night I had to use a public station on a long trip and saw that I had a choice of 150kw and 350kw. Other stations offer 50kw and 62.5 kw.

I used the 350kw one, plugged in for 31 minutes and my Bolt's range display went from 81 miles to 164 miles (whoa, that's faster than my Level 2 unit at home!) The cost was around $5 (Electrify Ameri

Q: in regular, practical terms, what do I need to know about choosing 50 vs 62.5 vs 150 vs 350? Should I always choose the highest kw so that it charges as fast as possible?

View attachment 34666

Thanks.
Well, if they're all available and there's no one waiting, the highest one is fine. The Bolt can charge, theoretically, at 55 kW, but a lot of public DCFC labeled 50 kW will only charge the Bolt at around 37 kW, because the charging station may calculate 50 kW = 100A x 500V. The Bolt's max charge rate is at 360V, so to get to 55 kW, you would need 150A. It's the amperage (150A) that's important.

It seems not all charging stations are labeled consistently, so it's possible that two different stations labeled 50 kW will charge a Bolt at different rates. Still, anything above 75 kW (150A x 500V) should max out the Bolt's charging capacity.
 

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The rated kW are misleading at times. The reality is, actually charge rates vary based on a number of conditions.

Most 50kW chargers are 100A @500V or 125A @400V. The Bolt's pack is less than 400V, so a 50 kW charger will not charge at 50kW on a Bolt, more like 37-45 kW in my experience.

Generally, any charger rated 62.5 and up will potentially yield the best charging speeds, because that would mean 150A which is the Bolt's max acceptance rate. The DCFC protocol handles voltage and amperage negotiation, up to the lesser of the car's or EVSE's capacity. It varies as SOC and conditions change.

Ambient temps, pack temps can also play a role. Ideal conditions are pack temps around 70F, outside of this, the acceptance rate drops, and thermal battery management consumes some power to try to reach or maintain optimal temps.

The short answer is, any 62.5 or greater EVSE should approach or reach Bolt's max potential in ideal temp conditions. An EVSE rated at higher kW will do no harm, because the Bolt negotiates the max Volts and Amps it can take given conditions.
 

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Excellent summary. Charging power nomenclature is frustrating. As I posted elsewhere this week: "Anyone with a noggin would think that a 50kW charging station would charge at 50kW. There is nothing further from the truth." with your explanation attached.

ga2500ev
 

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One thing is that they may all be doing something a bit different, even the same DC brand (e.g. Elec. Amer) at different locations. As long as we can tell the price before plugging in and I don't need to do five minutes of math. I could be saving 10 minutes on a 350 charger but it could cost twice as much. Some are by charge, some are by minutes, etc.
 

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If I understand correctly, my 2021 Bolt can fast-charge up to 50 kw. The other night I had to use a public station on a long trip and saw that I had a choice of 150kw and 350kw. Other stations offer 50kw and 62.5 kw.

I used the 350kw one, plugged in for 31 minutes and my Bolt's range display went from 81 miles to 164 miles (whoa, that's faster than my Level 2 unit at home!) The cost was around $5 (Electrify Ameri

Q: in regular, practical terms, what do I need to know about choosing 50 vs 62.5 vs 150 vs 350? Should I always choose the highest kw so that it charges as fast as possible?

View attachment 34666

Thanks.
Choose the 150 over the 350 so if a guy with a Taycan happens to show up while you're charging you might get to be friends. It's good to have as many friends with Taycans as possible.
 

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Well, if they're all available and there's no one waiting, the highest one is fine. The Bolt can charge, theoretically, at 55 kW, but a lot of public DCFC labeled 50 kW will only charge the Bolt at around 37 kW, because the charging station may calculate 50 kW = 100A x 500V. The Bolt's max charge rate is at 360V, so to get to 55 kW, you would need 150A. It's the amperage (150A) that's important.

It seems not all charging stations are labeled consistently, so it's possible that two different stations labeled 50 kW will charge a Bolt at different rates. Still, anything above 75 kW (150A x 500V) should max out the Bolt's charging capacity.
Liuelson is 100% correct. I usually get 35-40KW of charge at a 50KW station. I personally charge at 150KW chargers, as they always give my Bolt as many KW as it can take. I'd recommend it too.
Some EV owners get crabby if you take their nice and fancy 250KW or 350KW chargers, so I like to stay out of their way and pick the mid-range option.
 

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One thing is that they may all be doing something a bit different, even the same DC brand (e.g. Elec. Amer) at different locations. As long as we can tell the price before plugging in and I don't need to do five minutes of math. I could be saving 10 minutes on a 350 charger but it could cost twice as much. Some are by charge, some are by minutes, etc.
EA charges based on the advertised rate your car tells the EVSE. If you plug in to either 150kW or 350kW, Bolt will tell the EVSE it can take up to 55kW. And the Bolt will charge at the same speed on both as both plugs are capable of supplying more power than the Bolt can handle. It will then negotiate Volts and Amps to match the BMS analysis of what the car can take based on SOC, temps, etc. And it will continue to adjust this as the battery charges.

With kWh pricing, 1-350kW (car's advertised max charge rate) is the same price regardless of how fast you are actually able to charge. On timed, as long as your EV advertises less than 90kW, the lower price applies regardless of the EVSE capacity.

The only reasons to not use 350 are to leave that plug available for the EV that can charge at rates higher than 150, or the weight of the cord makes the initialization fail. The latter can generally be addressed by supporting the plug during initialization.
 

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I chose a 50 kW EV go charger last night that had 100 amp output. My SOC was 33% at start. I was charging at 40 kW For the first 12 minutes and that brought me to 49% and 9 kW charged. Forgive me if my terminology is off (i’m new to the board) but I wanted to try out EV go (they had an April special if you give them 10 minutes they’ll give you five dollars in May…)
 

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I chose a 50 kW EV go charger last night that had 100 amp output. My SOC was 33% at start. I was charging at 40 kW For the first 12 minutes and that brought me to 49% and 9 kW charged. Forgive me if my terminology is off (i’m new to the board) but I wanted to try out EV go (they had an April special if you give them 10 minutes they’ll give you five dollars in May…)
Right, and if you start at 33% or if it's 45-50 degrees outside, 40kW is about max. Sometimes I've needed to top-up in order to make routes feasible and for my 2020 it slows ultimately to 15kW at springtime temps, but at 80% it's more like 20-25. I've been surprised at how quickly it charges to 100% even at 45 degrees because after reading folks on this forum using words like "excruciatingly slow", I had low expectations, but 30 to 45 minutes with the 2020 and you're ready to cross vast un-electrified spaces.
 

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I chose a 50 kW EV go charger last night that had 100 amp output. My SOC was 33% at start. I was charging at 40 kW For the first 12 minutes and that brought me to 49% and 9 kW charged. Forgive me if my terminology is off (i’m new to the board) but I wanted to try out EV go (they had an April special if you give them 10 minutes they’ll give you five dollars in May…)
Terminologywise you almost got it right. It's 9 kWh charged. I use the mnemonic that kWh is gallons (like 10 gallons) and kW is gallons/min (The pump pumps 1 gallon per minute). The former tells you how much energy you have while the latter tells you how fast you can move energy from one place to the other.

ga2500ev
 

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The rated kW are misleading at times. The reality is, actually charge rates vary based on a number of conditions.

Most 50kW chargers are 100A @500V or 125A @400V. The Bolt's pack is less than 400V, so a 50 kW charger will not charge at 50kW on a Bolt, more like 37-45 kW in my experience.

Generally, any charger rated 62.5 and up will potentially yield the best charging speeds, because that would mean 150A which is the Bolt's max acceptance rate. The DCFC protocol handles voltage and amperage negotiation, up to the lesser of the car's or EVSE's capacity. It varies as SOC and conditions change.

Ambient temps, pack temps can also play a role. Ideal conditions are pack temps around 70F, outside of this, the acceptance rate drops, and thermal battery management consumes some power to try to reach or maintain optimal temps.

The short answer is, any 62.5 or greater EVSE should approach or reach Bolt's max potential in ideal temp conditions. An EVSE rated at higher kW will do no harm, because the Bolt negotiates the max Volts and Amps it can take given conditions.
I think a 62.5 kW station is likely to be 125A * 500V which will flow less than the Bolt's 55kW max. At least that's what I've experienced at my local ChargePoint DCFC that's rated at 62.5 kW. I've never been able to get the actual Amperage rating on it. Santa Cruz CA, 701 Ocean Street.
 

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I think a 62.5 kW station is likely to be 125A * 500V which will flow less than the Bolt's 55kW max. At least that's what I've experienced at my local ChargePoint DCFC that's rated at 62.5 kW. I've never been able to get the actual Amperage rating on it. Santa Cruz CA, 701 Ocean Street.
That may be true, I only used these once and didn't watch carefully but I seem to recall it was a bit over 50kW on the DIC. The user manual states 80kW or higher will reach top DCFC speeds.
 

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That may be true, I only used these once and didn't watch carefully but I seem to recall it was a bit over 50kW on the DIC. The user manual states 80kW or higher will reach top DCFC speeds.
To the OP's question: If his SOC is 50% or less and he wants the max charge rate, I'd recommend plugging into a 75kW or greater station. On the particular "62.5 kW" rated ChargePoint station that I mentioned, I've never been able to get more than 44kW which would be about 360V @ 125A.
 

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Just to echo what's been said already, if you have a choice between 75 kW or more or something less than 75 kW, pick 75 kW or more (because even though the Bolt only actually needs 55 kW at its peak you can't be sure you'll actually get 55 kW from a “60 kW” station).

But if a location has 150 kW and 350 kW, use the 150 kW as there's no point in hogging more kW than you can use, 150 kW is already more than double what you can actually use.
 
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