DC vs. AC Charging

iten

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So I keep hearing that fast charging is bad for EV batteries, but there are also some studies that suggests damage is negligible...

It seems that the logic is the excessive heat from the high rate of charge damages the battery modules, and not that DC is more damaging than AC charging.

My question is, if I use a "slow" DC charging station that gives between 12-24kwh, is the "damage" roughly the same as using a 11kwh / 22kwh(if it ever becomes available) AC Charger?

The reason I am asking is that there is this place that I spend 2 hours twice a week, providing free "slower" DC charging. I am wondering if I should rely heavily on it because my home and office only have level 1 wall sockets available.

Thanks!
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The battery is only charged by DC, (AC has to get rectified by the car), so it's all about the charge rate, C. At low C values (given how many packs there are), it'll be fine.

At low rates like you are talking about, it's not going to make a significant difference between DC and AC charging. The difference is that the charger is doing the rectification from AC to DC instead of the car.
 
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iten

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The battery is only charged by DC, (AC has to get rectified by the car), so it's all about the charge rate, C. At low C values (given how many packs there are), it'll be fine.

At low rates like you are talking about, it's not going to make a significant difference between DC and AC charging. The difference is that the charger is doing the rectification from AC to DC instead of the car.
Thanks Miwa!
 

Gogs

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So I keep hearing that fast charging is bad for EV batteries, but there are also some studies that suggests damage is negligible...

It seems that the logic is the excessive heat from the high rate of charge damages the battery modules, and not that DC is more damaging than AC charging.

My question is, if I use a "slow" DC charging station that gives between 12-24kwh, is the "damage" roughly the same as using a 11kwh / 22kwh(if it ever becomes available) AC Charger?

The reason I am asking is that there is this place that I spend 2 hours twice a week, providing free "slower" DC charging. I am wondering if I should rely heavily on it because my home and office only have level 1 wall sockets available.

Thanks!
Anything above 50KW is really pumping in power to the battery. But the car software will deal with that. I would not worry about regular 50kW charging. Much worst if you fill the car 100% and leave it at 100% longer than a few hours.
 

daveo4EV

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let the battery management software do it's thing and don't worry about it - it's pretty clear that unless Porsche really screwed up (unlikely) the battery will last much longer than you'll own the car - and the warranty is generous - it's the job of the Battery Management Software to not "overtax" the battery -and controlling temperature and charge rate the BMS can easily make sure the battery is well managed and should last for many years…
 


HK111

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Much worst if you fill the car 100% and leave it at 100% longer than a few hours.
Are you sure about this?
 

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Are you sure about this?
Absolutely, daily charging is recommended at 85%. Obviously for toad trips you will charge to 100% on a timed profile allowing you to sit at 100% for the minimum amount of time.
 

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Absolutely, daily charging is recommended at 85%. Obviously for toad trips you will charge to 100% on a timed profile allowing you to sit at 100% for the minimum amount of time.
It's not a tesla though so 100% isn't really 100% - there's always a top buffer and this drastically reduces the impact of having the battery fully charged
 


Gogs

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The use manual says 85% pal, I realise there is a buffer, but I'd rather stick to that then make assumptions on battery capacity. Things might change when I get used to charging and understanding capacity more.
 

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The use manual says 85% pal, I realise there is a buffer, but I'd rather stick to that then make assumptions on battery capacity. Things might change when I get used to charging and understanding capacity more.
I know the manual however recommending 85% day to day is a world away from
Much worst if you fill the car 100% and leave it at 100% longer than a few hours.
That is just scaremongering.
the turbo s battery pack is 93.4 kWh with 83.7kwh - so full charge wont even go to 90%.
 

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I know the manual however recommending 85% day to day is a world away from

That is just scaremongering.
the turbo s battery pack is 93.4 kWh with 83.7kwh - so full charge wont even go to 90%.
I’d assume that 5kWh is reserved at the top, and 5kWh at the bottom. (Not based on facts, purely an assumption of: 0% is death for a battery, and long term storage at 100% isn’t recommended.)
 

daveo4EV

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I have zero concern leaving a Porsche/Bolt sitting at 100% - I'm pretty sure it's not really 100% - both companies are pretty conservative with the battery management…

Tesla - best to charge to 100% only when needed, and don't leave the car sitting at 100% for to long - it's bad for LiON to be left sitting at 100% charge…
 

Gogs

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I have zero concern leaving a Porsche/Bolt sitting at 100% - I'm pretty sure it's not really 100% - both companies are pretty conservative with the battery management…

Tesla - best to charge to 100% only when needed, and don't leave the car sitting at 100% for to long - it's bad for LiON to be left sitting at 100% charge…
Good luck
 

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I know the manual however recommending 85% day to day is a world away from

That is just scaremongering.
the turbo s battery pack is 93.4 kWh with 83.7kwh - so full charge wont even go to 90%.
Exactly. I will always charge the car to 100%, but then I will not charge it every night. I expect the lifetime of the battery sufficient for me and the next owner.
 

Gogs

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I hope your right and the battery will last, but if you do have a problem with the power pack, then good luck claiming on the warranty when you have not followed the instructions provided. They will wriggle out of that easily by checking the logs. But I do understand your methodology, I'm just more cautious.
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