[Darren Donovan]

I've seen 2 numbers associated with the Bolt.
11 kW, and 55 kW

I saw a public charging station outside of a Denny's restaurant, stopped by to look at the spec. It read "50 kW". This station only charges $0.50 per hour to charge.

So if I hook up my future Bolt EUV to it, will I get 11 kW/hour delivered to the battery, or will I get 50 kW/hour? I know there are losses due to battery SOC and other factors, so the numbers I posted are ideal/theoretical. Let's assume there's no loss to make it easier to understand.

Thanks!

 

[Willie]

If it's a DCFC station, then about 50 kW is possible (100 miles in 30 min to quote Chevy); if it's a Level 2 station, then up to 11 kW is possible, but probably more like 6 to 7 kW, so 20 to 25 miles per hour of charging.

 

[Electric Personality]

You rarely get 50 kw from dc charging.
You may from 10 to 60% if the battery is warm and you dance a jig.

 

[cwerdna]

No. Bolt charges at up to 54 or 55ish kW, not 50. I've hit those rates.

So if I hook up my future Bolt EUV to it, will I get 11 kW/hour delivered to the battery, or will I get 50 kW/hour?

This isn't a correct question. This makes no sense in the context of EVs.

See Level 3 Charging Speed(s) on 2020. I'd write more but have other things going over here right now.

 

[PA Bolt EV]

I've seen 2 numbers associated with the Bolt.
11 kW, and 55 kW

So if I hook up my future Bolt EUV to it, will I get 11 kW/hour delivered to the battery, or will I get 50 kW/hour?

The "new" 2022 - 2023 Bolts have a Level 2 charger capable of 11 kW, and a DCFC (DC Fast Charge) capability of 55 kW. The one at the Denny's you mention would be DCFC.

How much will get into your battery will vary. Level 2 will almost always put in the maximum kW the station is capable of. DCFC varies depending on the cars current battery temperature, SOC (state of charge), etc.

 

[jefro]

Yes and no. On a 50kW charger you might get anywhere between 10 and 54 kW rates. My car has never been below 10 and that would be if I am near the full battery charge. Basically for the fastest charge speeds (as measured in kW) on DC fast charger your battery needs to be about 18% up to about 55%. Any temperature extreme or deviation of charge will reduce that speed.

So, you can get it under some conditions. You on a current Bolt won't get it for use of average.

 

[Voldar]

I saw a public charging station outside of a Denny's restaurant, stopped by to look at the spec. It read "50 kW". This station only charges $0.50 per hour to charge.

So if I hook up my future Bolt EUV to it, will I get 11 kW/hour delivered to the battery, or will I get 50 kW/hour?

The correct answer is neither.
A 50 kW DCFC can only provide max 50 kW. It can't deliver 55 kW.
The Bolt EV on a 50 kW DCFC will receive about 44-45 kW in the 0%-50% SOC battery range, if the amperage of the station is 125A (or about 35-37 kW if the amperage of the station is 100A). It will deliver less than 11 kW if you are charging the Bolt EV in the 95-100% SOC range.

 

[Zapster]

I think the key figure is not 50kW but 50 cents. If it's 50 cents per kilowatt, then it's likely Level 3. If it's 50 cents per hour, then I suspect the unit is a mislabeled Level 2.

 

[md.]

There are basically three types of EV chargers: Level 1, Level 2, (which are both AC) and Level 3 (also known as DC Fast Charging).

The Bolt has a charger built into the car that is capable of Level 1 charging (generally 120 V AC, usually at home) and Level 2 charging (generally 240V AC, can be at home or public chargers). The maximum capability of the Bolt EUV's built-in Level 1/Level 2 charger is 11kW, which you get by running 48 amps at 240 volts. Multiply 48 x 240 to get 11,520 watts or 11.5kW. Lower amps or 120V will give you less kWs. For example, the dual-voltage cord that comes with the Bolt EUV charges up to 12A at 120V (1.4kW) or 32A at 240V (7.7kW).

Level 3 (DCFC) is only available as public chargers. At this time, if you see something above 19.2kW, it's almost certainly DCFC. Some of the DCFCs that you find will be rated for 25kW, 50kW, 150kW, or 350kW. The maximum capability of the Bolt is to receive 55kW. So, on a 25kW DCFC station, it will max out at 25kW. At a 50kW, it will max out at 50kW. At a 150kW or 350kW station, it will max out at 55kW. (It's a little more complicated than that, but those are the basics.)

To summarize, 11kW is the maximum capacity of the Level 2 charger built into the vehicle. 55kW is the maximum power that the vehicle can accept from a public DC Fast Charging station. For that station, if your numbers are correct, it's a DCFC station and you'll max out at something below 50kW. And Denny's is subsidizing your charging by charging you a very low rate for DCFC.

Now, to get the full 55kW charging speed, conditions need to be perfect. Warm-ish temperature, and your battery has to be in a low-ish State of Charge. As the SoC approaches 50%, the charging speed slows down until it is almost useless to keep charging past 80% SoC. See an example image of charging power below from this article.

How Long Does It Take To Charge a Chevrolet Bolt EV?

We completely drain the battery of a 2017 Chevrolet Bolt EV and then record the full 0% to 100% charging session to find out how long it takes to charge.

insideevs.com

 

[Martin D]

All the numbers and math turns into the real issue which is the 50 kW charger will mean that you can go maybe 100-150 miles to the lunch stop after eating a Denny’s breakfast, unless the waitress has too many tables to take care of or the meal is inhaled. Have a third cup of coffee and relax for a bit. What’s the rush while your Bolt has breakfast?

The level 2 charger might mean that lunch is going to be about 15 minutes later, so you might as well just walk over to McDonald’s from Denny’s. Or get a room because dinner is right after lunch at 25-30 miles added per hour of charging.

 

[pooge30]

Whatch Tom M on his youTube channel, State of Charge.

 

[Kbecker]

There are so many factors that it’s hard to know for sure what that charger will give you, until you try it. Look at the connector. Does it just have the round plug that fits in the top half of your charging port? Or does it have the larger plug that engages the extra two holes at the bottom? If it’s just the round plug, it will max at 11kw. If it’s the larger one it will max at 55kw.

In the real world, though, you usually get less than the max.

My advice is, try it and see. That is the only way to know for sure, and it’s not like it’s expensive.

 

[PDX Bolt]

When the DCFC speed on the Bolt is referenced as “55 kW”, I think you need to think of it in the same way one must approach how internet speeds are advertised by telecom companies…. They are invariably preceded by the pesky qualifier “up to….”.

 

[ehidle]

Lithium battery designer here...

The two rates are for Level 2 and Level 3 chargers. A Level 2 charger provides 240VAC to the vehicle and its on-board AC to DC converter charges the batteries. A Level 3 charger provides high voltage DC directly to the battery pack and communicates with the battery management system directly. The latter (Level 3) is capable of much higher power because of the higher voltage applied.

The reason you see the 55kW rate fall off at approximately 50% SoC is because the cells have gone from "Bulk" charge to "Absorption" charge. Here are the stages of lithium charging explained:

1) Conditioning charge: This happens at extremely low SoC. The current is small, and the purpose is to take a very dead battery and condition it to be able to accept a higher rate of charge. If you attempt to charge a very dead battery quickly, it will overheat.

2) Bulk Charge: This happens between low SoC and about 50% SoC. During this phase, a constant current is delivered to the battery. The voltage on the cells is increasing during this phase. The end of this phase of charge occurs when the cells reach approximately 4.2V per cell, the "terminal voltage." The voltage on the cells cannot be pushed any higher without damaging them or risking a fire.

3) Absorption Charge: This phase begins when the cells reach terminal voltage. The charger holds the voltage constant and delivers whatever current will continue to flow into the battery. As the batteries continue to charge, the current drops. This is called the "taper." As the current tapers off, the cells are reaching their full state of charge

4) Float: This is not really a charging phase, but the cells are basically held at their termination voltage at very low current. Lithium batteries do not actually need a "float" charge like traditional lead-acid batteries do. Most lithium-specific chargers do not include a float phase, but rather start an absorption phase periodically.

Our Bolts have 96 lithium cells in series, to make 403.2 volts at full charge. The BMS will allow a discharge rate of up to 160kW at full charge, approximately 400 amps from the battery pack.

I hope this helps

 

[jefro]

Electric car charging cost and time calculator

evcompare.io

 

[Voldar]

@jefro I think your answer should go the other thread.

 

[GregBrew]

Repeat after me..."DCFC not Level 3"..."DCFC not Level 3"..."DCFC not Level 3"...

 

[cwerdna]

I think the key figure is not 50kW but 50 cents. If it's 50 cents per kilowatt, then it's likely Level 3. If it's 50 cents per hour, then I suspect the unit is a mislabeled Level 2.

Huh? Seems like you have a bunch of unit confusion.

What does "50 cents per kilowatt" mean? Can you give us an example of that somewhere like on Plugshare?

 

[Zapster]

Huh? Seems like you have a bunch of unit confusion.

What does "50 cents per kilowatt" mean? Can you give us an example of that somewhere like on Plugshare?

Fine, Andrew, 50 cents per kWh. Feel better?

 

[ga2500ev]

Fine, Andrew, 50 cents per kWh. Feel better?

This seems insignificant, but it isn't. If someone said they were buying gas at 10 gallons per minute, you'd immediately recognize that doesn't make any sense. But it's literally the difference between Kw (a rate that electricity is transferred) and kWh (the energy capacity of the electricity that is transferred).

ga2500ev