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Discussion Starter #1
While driving my Bolt EV back home, I made an interesting discovery. The max regenerative braking power is at least 70 kW. I could be more--if it is based on battery SOC--, but between 50-70% state of charge, it maxes out at 70 kW.
 

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That isn't a clear indication if the battery will allow a 70 kW DC charge. GM has to specify the real power limit.
 

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That isn't a clear indication if the battery will allow a 70 kW DC charge. GM has to specify the real power limit.
Oh, I wasn't implying that it was, but I've seen posts floating around stating that the max regen for the Bolt EV is locked at 60 kW. That is not the case. I don't know if it goes up or down from 70 kW based on SOC or conditions, but I know that the max regen is at least 70 kW.
 

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That isn't a clear indication if the battery will allow a 70 kW DC charge. GM has to specify the real power limit.
It's on pg 232 of the OM, "at least 80kW". Will it charge faster than 180 miles per hour? We will have to wait for higher CCS stations to learn the truth.
 

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On Volt, the 60KW regen is limited to 10 seconds, I believe. Which is about a 3.3C rate. So 70KW on Bolt is a real gentle 1.2C. Anyone know what max regen is on a Tesla?
 

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Anyone know what max regen is on a Tesla?
60kW

The max regenerative braking power is at least 70 kW. I could be more--if it is based on battery SOC--, but between 50-70% state of charge, it maxes out at 70 kW.
I assume you were in L mode with the Regen on Demand (RoD) paddle activated? What was the highest speed you started from to attempt max regen?

If you didn't try it above 75 mph, you might be able to get more than 70kW. SoC shouldn't matter, as long as the battery is warm and there's less than 100% SoC.

My coastdown model says max regen should be a little over 75kW at 75 mph or higher, but I set those results aside. I figured there was an error since I thought they were going to limit regen to 60kW.

If my model is close, regen would be above 70kW until you decelerate below 50 mph.
 

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Discussion Starter #7
60kW

I assume you were in L mode with the Regen on Demand (RoD) paddle activated? What was the highest speed you started from to attempt max regen?

If you didn't try it above 75 mph, you might be able to get more than 70kW. SoC shouldn't matter, as long as the battery is warm and there's less than 100% SoC.

My coastdown model says max regen should be a little over 75kW at 75 mph or higher, but I set those results aside. I figured there was an error since I thought they were going to limit regen to 60kW.

If my model is close, regen would be above 70kW until you decelerate below 50 mph.
You are correct. In L using the RoD paddle. I was only doing 55 MPH or so, but I was descending a 4-6% grade at the time, which could have had an effect. I was able to recreate the 70 kW regen experience several times. I wasn't paying attention to speed, but I believe one was definitely below 45 mph (but again, going down hill).
 

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On Volt, the 60KW regen is limited to 10 seconds, I believe. Which is about a 3.3C rate. So 70KW on Bolt is a real gentle 1.2C. Anyone know what max regen is on a Tesla?
60kW for 10 seconds was also the max on a Gen 1 Volt, which is a 3.75C rate when paired with the initial model year's 16kWh battery.
 

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60kW for 10 seconds was also the max on a Gen 1 Volt, which is a 3.75C rate when paired with the initial model year's 16kWh battery.
Yeah I've overrun that a few times coming down a 10% grade near where I work. (2013 Gen 1).
I didn't actually time it, but it seems to "reset" after about 15-20 seconds of "cool down" time.
 

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60kW for 10 seconds was also the max on a Gen 1 Volt, which is a 3.75C rate when paired with the initial model year's 16kWh battery.
I wonder how a Gen 1 Volt could do 60kW regen when MGA (generator motor) is rated at 55kW. In the many years I used my Gen 1 (2013) Volt, I have never seen regen go over 55kW, even when checked via OBDII
 

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It's likely software limited at high SOC% to prolong battery life. Much like how DCFC tapers above 80%.

I wonder how a Gen 1 Volt could do 60kW regen when MGA (generator motor) is rated at 55kW. In the many years I used my Gen 1 (2013) Volt, I have never seen regen go over 55kW, even when checked via OBDII
MGB is rated at 110kW and is always connected to the wheels.
Even then, motors aren't too particular about exceeding their rated values for short periods (within reason, not like 10x).

I have seen it hit 60 occasional. By far the norm is 55 max.
IIRC all the times I've seen 60 it has been in a combined mode (both motors connected in the transmission, with or without engine on) going down a hill at a decent speed and coming to a stop before it could clutch out the second motor.
 
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