Infinion
Posts: 33
Joined: Thu Aug 20, 2020 2:59 pm
Location: Burnaby, BC

Re: DCFC message 'Charging rate limited to 30% at vehicles request'

Sun Oct 17, 2021 10:33 am

My guess would be that the battery pack is "coldgating".
If it's a cold morning and batteries are very cold or near freezing, like 32ºF/0ºC - 5ºC region or less, fast charging could irreversibly damage the batteries as the lithium ions would be electroplated permanently, rather than intercalate which is reversible.

To prevent the ions from plating into a useless hunk of metal and degrade the capacity by half or more, a precautionary reduction in charge rate is applied which gives the battery heater (I think it's 2kW?) time to bring the batteries to a warmer temperature where you can get your full 50kW 3C charging. Chargers will usually follow the JEITA standard to help shape the throttling when the electrochemistry is sluggish from cold weather, but GM/LG could very well be following a custom profile


Throttling also happens when the batteries are too hot. Rule of thumb is that batteries like to be as warm as people, so somewhere in the range of 12ºC - 38ºC is the goldilocks zone for happy batteries.

SparkE
Posts: 451
Joined: Tue Sep 06, 2016 1:18 am
Location: SF Bay Area (San Jose, CA)

Re: DCFC message 'Charging rate limited to 30% at vehicles request'

Sun Nov 07, 2021 8:58 am

Not enough info in the original report to help you. ( "g" ?? )

I did have a situation a few months ago where some EA (Electrify America) DCFC chargers would only charge my spark at 16 kW. And it was definitely the charger, as I had charged at a ChargePoint 24 kW charger at 22 kW (low battery SoC in my vehicle) for about 15 minutes earlier before moving to the "150 kW" charger. I then drove down the road 15 miles to another (different brand) EA DCFC and it charged at around 53 kW. EVERY one of the same brand DCFC that night charged at 16 kW "at request of vehicle" (which was B.S.). This was the weekend back in July when EA was offering free charging, so I tried out a bunch of chargers (about 6) on the way up and back from northern SF bay area. The one brand DCFC (BTCPower 150 kW units ) just wouldn't charge at full speed, even though other EA fast chargers did (SIGNET 150 kW, for example).

Infinion
Posts: 33
Joined: Thu Aug 20, 2020 2:59 pm
Location: Burnaby, BC

Re: DCFC message 'Charging rate limited to 30% at vehicles request'

Sun Nov 07, 2021 10:56 am

SparkE wrote:
Sun Nov 07, 2021 8:58 am
Not enough info in the original report to help you. ( "g" ?? )

I did have a situation a few months ago where some EA (Electrify America) DCFC chargers would only charge my spark at 16 kW. And it was definitely the charger, as I had charged at a ChargePoint 24 kW charger at 22 kW (low battery SoC in my vehicle) for about 15 minutes earlier before moving to the "150 kW" charger. I then drove down the road 15 miles to another (different brand) EA DCFC and it charged at around 53 kW. EVERY one of the same brand DCFC that night charged at 16 kW "at request of vehicle" (which was B.S.). This was the weekend back in July when EA was offering free charging, so I tried out a bunch of chargers (about 6) on the way up and back from northern SF bay area. The one brand DCFC (BTCPower 150 kW units ) just wouldn't charge at full speed, even though other EA fast chargers did (SIGNET 150 kW, for example).
I just want to point out and appreciate, that even when the Spark is not doing what it should, it still manages to charge cells faster than its successor at over 1C (for most of us that have had some degradation).

It's really strange regarding the 16kW DCFC. After that day, did it continue to charge at the slower rate at BTCPower DCFC's?
It seems like if its charger specific, it would be a communication issue. You said somewhere else that you had the 2014 Spark, right? I wonder if the communication protocol gets updated along with a software update with the head unit.

If you check out viewtopic.php?f=9&t=4056 I wonder what version you have and if that would affect DCFC in a meaningful way.


MrDRMorgan
Posts: 1191
Joined: Wed Oct 30, 2013 7:27 am
Location: Manteca in Central California

Re: DCFC message 'Charging rate limited to 30% at vehicles request'

Sun Nov 14, 2021 4:52 pm

I just happened to see this thread and I found it interesting. Recently, I tried DCFC charging at EA stations in Livermore and in Castro Valley and my charging was limited to 16kwh. Both of these locations had previously worked without a problem. Fortunately, I found an EvGo charger in Castro Valley that worked just fine - even though it looked to be one of the new chargers.

These two locations are, respectively, 40 and 50 miles from my home so I may have to make a day trip and try again.

LoveMy2014SparkEV
Posts: 5
Joined: Fri Nov 12, 2021 9:55 pm

Re: DCFC message 'Charging rate limited to 30% at vehicles request'

Sun Nov 14, 2021 11:50 pm

@MrDRMorgan,
I took a look on PlugShare and the EA chargers in Castro Valley sure look like BTCPower chargers to me. I also looked at the EVgo in Castro Valley as well and they don't look like the EVgo chargers I been to. I searched high and low in my area at all the EVgo chargers trying to find any that didn't use the BTCPower chargers but so far no luck. Around here they all use the same model.

I have a 2014 Spark EV. I only get 14 kW or 15 kW charging at all the BTCPower chargers no matter who owns them. I have tried them at Electrify America, EVgo and CalTrans both 40 kW and 150 kW chargers. The ABB chargers at Electrify America I had connection problems until I modified my charging port as described here https://sparkev.blogspot.com/2015/09/so ... e.html?m=1 .

I been to the Electrify America station that has ABB chargers twice now trying two different chargers after the modification and both worked on the first try and charged me at 51 kW. :D I had heard that you can get a communications error if you swipe the app too soon to initialize charging. They said after plugging in your car wait till the screen on the charger comes up with the instructions to pay with your credit card then swipe initialize on your app. So I tried to make it fail by swiping the app as soon as it I could. The screen on the charger was still in the communication phase and hadn't gotten to the credit card part. It didn't cause an error and the charge went normally and charged my car at 51 kW rate. Only other thing I can think of is I did have my blue tooth turned off on my phone. I had heard that can help if you turn it off.

I stopped at a ChargePoint to see if I can charge at 50 kW or if they too would limit my charge to 14 kW. I had trouble with the app trying to setup my payment and the ChargePoint charger didn't accept credit cards. So I had to give up and go home.

So far it looks like a BTCPower software issue. Perhaps the 2014 Spark EV needs an update in its firmware or BTCPower needs to update their software to make sure it is backwards compatible with older EVs. This will be an issue charging companies will have to face more and more as the years go on.

LoveMy2014SparkEV
Posts: 5
Joined: Fri Nov 12, 2021 9:55 pm

Re: DCFC message 'Charging rate limited to 30% at vehicles request'

Mon Nov 15, 2021 10:37 pm

UPDATE: 11/15/2021

I went to two different Electrify America stations on the other side of town. I wanted to try charging on different model and make of chargers to see if my car would charge at 50kW on other chargers other than ABB chargers. The first Electrify America had Signet HDP350K-NCM2 chargers. These are really nice chargers and very quiet. My 2014 Spark EV charged at 51kW on the first try. :D I then went to the second Electrify America station and it too had Signet chargers but a different older model DP350K-DCM. My first two attempts failed. :( Being an older station and well weather beaten I tried another charger at the same location and it worked perfectly. :D It charged at 51kW first try. I think my first tries failed because of wear and tear on the equipment, stiffness of the cord which put an unusual amount of strain on the plug as I had to twist it 180 degrees. The second charger because of the way it was placed I had to park on the back side. This turned out to be a good thing since I didn't have to twist plug and thus less stress on the connection. I like being able to see the screen from inside the car but if it mean less stress on the connection I can live with it.

I plan on going to another EVgo location soon which has different models of chargers than the BTCPower chargers that have been limiting me to 15kW. I also plan on trying a ChargePoint charger. After that I will have a pretty good idea of what chargers to avoid if I am in a hurry.

I can't say this enough, I really think the modification I did on my charging port really helped with my connections errors I was getting. https://sparkev.blogspot.com/2015/09/so ... e.html?m=1

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