Charging and OBC discussion split from Nissan Ariya thread

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knightmb

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Messages
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Franklin, TN
[mod note: split from https://mynissanleaf.com/viewtopic.php?f=17&t=31210&start=230#p610212]


DaveinOlyWA said:
knightmb said:
An 800V DC fast charger could still charge a 350V, 360V, or 375V battery. Nissan is using 500V to charge their 360V battery with CHAdeMO. How much voltage is actually needed to charge an 800V battery? 1000V?

I thought the limitation on charging was the battery chemistry in terms of power not the voltage? If you feed 1000V @ 50A into any of those batteries, they will all charge at the same rate of 50 kW per second. I understand using higher voltage to reduce the size of wires in the electrical system of the EV for both driving and charging, but how does that exclude the higher voltage charging for the lower voltage batteries?

uhhh...no. You "can't" put a 1000 volts into the LEAF pack no matter what. so 1000 volts @ 50 amps won't get you 50 kw. Might get 19 lw but that's about it. This is the reason that I only rate DC chargers by current.
This would be the wrong place to discuss that topic. ;)
P = V * I so yeah, 1000v x 50 amps = 50,000 watts, the math is right. Doesn't mean you should put that into a Leaf pack, I thought the discussion was about the 800V EV?
 
knightmb said:
DaveinOlyWA said:
knightmb said:
An 800V DC fast charger could still charge a 350V, 360V, or 375V battery. Nissan is using 500V to charge their 360V battery with CHAdeMO. How much voltage is actually needed to charge an 800V battery? 1000V?

I thought the limitation on charging was the battery chemistry in terms of power not the voltage? If you feed 1000V @ 50A into any of those batteries, they will all charge at the same rate of 50 kW per second. I understand using higher voltage to reduce the size of wires in the electrical system of the EV for both driving and charging, but how does that exclude the higher voltage charging for the lower voltage batteries?

uhhh...no. You "can't" put a 1000 volts into the LEAF pack no matter what. so 1000 volts @ 50 amps won't get you 50 kw. Might get 19 lw but that's about it. This is the reason that I only rate DC chargers by current.
This would be the wrong place to discuss that topic. ;)
P = V * I so yeah, 1000v x 50 amps = 50,000 watts, the math is right. Doesn't mean you should put that into a Leaf pack, I thought the discussion was about the 800V EV?

Ariya? Pretty sure its still 400
 
knightmb said:
DaveinOlyWA said:
uhhh...no. You "can't" put a 1000 volts into the LEAF pack no matter what. so 1000 volts @ 50 amps won't get you 50 kw. Might get 19 lw but that's about it. This is the reason that I only rate DC chargers by current.
This would be the wrong place to discuss that topic. ;)
P = V * I so yeah, 1000v x 50 amps = 50,000 watts, the math is right. Doesn't mean you should put that into a Leaf pack,
What do you mean in the bolded statement ?
Are you talking about some future LEAF that has a 1000v pack, or a current LEAF ?
 
SageBrush said:
knightmb said:
This would be the wrong place to discuss that topic. ;)
P = V * I so yeah, 1000v x 50 amps = 50,000 watts, the math is right. Doesn't mean you should put that into a Leaf pack,
What do you mean in the bolded statement ?
Are you talking about some future LEAF that has a 1000v pack, or a current LEAF ?
Current Leaf pack. I don't want to derail the discussion about the Ariya as this side topic has come up here about how much voltage you can feed into a battery. :?
 
knightmb said:
SageBrush said:
knightmb said:
This would be the wrong place to discuss that topic. ;)
P = V * I so yeah, 1000v x 50 amps = 50,000 watts, the math is right. Doesn't mean you should put that into a Leaf pack,
What do you mean in the bolded statement ?
Are you talking about some future LEAF that has a 1000v pack, or a current LEAF ?
Current Leaf pack.
The current LEAF is a 96S pack architecture so about 400 Volts at full SoC but the current tapers past ~ 370 volts
Nissan has never mentioned a different pack architecture for the Ariya, so presume 96S until proven otherwise.

I think I read Max 250 Amps electronics in the Ariya. so IF the CHAdeMO station/cable/plug supports 250 Amps the Ariya would peak at 250*0.37 = 92 kW. At other CHAdeMO locations with different Max Amps:
100 Amps: 37 kW
125 Amps: 46 kW
150 Amps: 55 kW
200 Amps: 74 kW
 
From March 29th:
The new Nissan will offer a 7.2 kW charging rate on Level 2 AC, and a 130 kW rate on DC.
https://chargedevs.com/newswire/nissan-releases-photos-and-details-of-2022-ariya-electric-suv/


Given the large 90kWh (87kWh usable) pack (and somewhat for the smaller 65kWh, 63 usable) the charging rates seem too low, particularly L2. Everyone else has gone to 40 or 48A OBCs for packs this size, with the Lucid going back to the 80A that Tesla offered on the S way back when, so 30 or maybe 32A before overhead and losses just doesn't cut it any more. It won't fully charge the car in 8 hours.
 
GRA said:
From March 29th:
The new Nissan will offer a 7.2 kW charging rate on Level 2 AC, and a 130 kW rate on DC.
https://chargedevs.com/newswire/nissan-releases-photos-and-details-of-2022-ariya-electric-suv/


Given the large 90kWh (87kWh usable) pack (and somewhat for the smaller 65kWh, 63 usable) the charging rates seem too low, particularly L2. Everyone else has gone to 40 or 48A OBCs for packs this size, with the Lucid going back to the 80A that Tesla offered on the S way back when, so 30 or maybe 32A before overhead and losses just doesn't cut it any more. It won't fully charge the car in 8 hours.
Doesn't cut it? While it would be nice to have a higher rate over J1772 but there's very little public J1772 infrastructure in the US that's above 30 or 32 amps. And, much of it is only 208 volts.
 
cwerdna said:
GRA said:
From March 29th:
The new Nissan will offer a 7.2 kW charging rate on Level 2 AC, and a 130 kW rate on DC.
https://chargedevs.com/newswire/nissan-releases-photos-and-details-of-2022-ariya-electric-suv/


Given the large 90kWh (87kWh usable) pack (and somewhat for the smaller 65kWh, 63 usable) the charging rates seem too low, particularly L2. Everyone else has gone to 40 or 48A OBCs for packs this size, with the Lucid going back to the 80A that Tesla offered on the S way back when, so 30 or maybe 32A before overhead and losses just doesn't cut it any more. It won't fully charge the car in 8 hours.
Doesn't cut it? While it would be nice to have a higher rate over J1772 but there's very little public J1772 infrastructure in the US that's above 30 or 32 amps. And, much of it is only 208 volts.


Public charging will also need to be boosted in power output, given that BEV packs will be growing in capacity for some time yet, and you can get away with fewer but individually more powerful L2 chargers if cars only need to charge at multi-day intervals. The 65kWh Bolt & EUV are using 48A OBCs, and cars with bigger packs will benefit even more. I consider 40A a practical minimum L2 for future BEVs, unless the public is willing to accept small battery BEVs for local use. There's no indication that they are so willing. PHEVs can get away with 16A or even L1 @ 12A, although 30-32A L2 would allow considerably more AE use, providing an approximate two-hour full charge.
 
GRA said:
From March 29th:
The new Nissan will offer a 7.2 kW charging rate on Level 2 AC, and a 130 kW rate on DC.
https://chargedevs.com/newswire/nissan-releases-photos-and-details-of-2022-ariya-electric-suv/


Given the large 90kWh (87kWh usable) pack (and somewhat for the smaller 65kWh, 63 usable) the charging rates seem too low, particularly L2. Everyone else has gone to 40 or 48A OBCs for packs this size, with the Lucid going back to the 80A that Tesla offered on the S way back when, so 30 or maybe 32A before overhead and losses just doesn't cut it any more. It won't fully charge the car in 8 hours.
Unless you hardwire the L2 charger, you're limited to a 50 amp plug. furthermore if you are drawing current for more than 3 hours, you're limited to 40 amps max out of that plug or 9.6 KW. There are plug-in chargers that can do that. Now assuming a100KH battery and 80% discharge (90%-10%), 90% efficiency and 240VAC, you need 9.5 hours to charge back to 90%. If you use a 32A charger instead then you're looking at 11.5 hours. Either way, plug it in when you get home and you'll be charged up in the morning. And who says you have to have a full charge in the morning anyway? Won't 60-70% be enough for the day? And how often are likely to discharge to 10% or less.

DCFC charging rates might be a problem if you're pressed for time, but overnight charging with a typical L2 isn't a problem.
 
I would hope that if someone is driving 300 miles a day for work, they have a way to QC somewhere along the way or L2 at work no matter what EV they are driving. :lol:
 
cwerdna said:
GRA said:
From March 29th:
The new Nissan will offer a 7.2 kW charging rate on Level 2 AC, and a 130 kW rate on DC.
https://chargedevs.com/newswire/nissan-releases-photos-and-details-of-2022-ariya-electric-suv/


Given the large 90kWh (87kWh usable) pack (and somewhat for the smaller 65kWh, 63 usable) the charging rates seem too low, particularly L2. Everyone else has gone to 40 or 48A OBCs for packs this size, with the Lucid going back to the 80A that Tesla offered on the S way back when, so 30 or maybe 32A before overhead and losses just doesn't cut it any more. It won't fully charge the car in 8 hours.
Doesn't cut it? While it would be nice to have a higher rate over J1772 but there's very little public J1772 infrastructure in the US that's above 30 or 32 amps. And, much of it is only 208 volts.
Lost in the discussion about how beefy an OBC to put in EVs is whether existing home electric panels can support it.
 
knightmb said:
I would hope that if someone is driving 300 miles a day for work, they have a way to QC somewhere along the way or L2 at work no matter what EV they are driving. :lol:

Exactly
 
jlv said:
7.2kW OBC "doesn't cut it"?
Spoken like a non-BEV driver.

More like a non-BEV driver who ass-umes that everybody drives 300 miles a day, 365 days a year.
 
I think it's clear to all but a few of us here (ahem, you know who you are...) that the bump to 7.2kw is a nice and very likely adequate feature improvement. We have a 50 amp service installed in our garage, so we could take advantage of it. I believe some of the other makes are talking about 11kw OBCs, but the real need much above 9 is dubious for home use in my view.

Not that concerned with public infrastructure for reasons I've noted often enough, and that goes doubly for L2 charging.
 
johnlocke said:
GRA said:
From March 29th:
The new Nissan will offer a 7.2 kW charging rate on Level 2 AC, and a 130 kW rate on DC.
https://chargedevs.com/newswire/nissan-releases-photos-and-details-of-2022-ariya-electric-suv/


Given the large 90kWh (87kWh usable) pack (and somewhat for the smaller 65kWh, 63 usable) the charging rates seem too low, particularly L2. Everyone else has gone to 40 or 48A OBCs for packs this size, with the Lucid going back to the 80A that Tesla offered on the S way back when, so 30 or maybe 32A before overhead and losses just doesn't cut it any more. It won't fully charge the car in 8 hours.
Unless you hardwire the L2 charger, you're limited to a 50 amp plug. furthermore if you are drawing current for more than 3 hours, you're limited to 40 amps max out of that plug or 9.6 KW. There are plug-in chargers that can do that. Now assuming a100KH battery and 80% discharge (90%-10%), 90% efficiency and 240VAC, you need 9.5 hours to charge back to 90%. If you use a 32A charger instead then you're looking at 11.5 hours. Either way, plug it in when you get home and you'll be charged up in the morning. And who says you have to have a full charge in the morning anyway? Won't 60-70% be enough for the day? And how often are likely to discharge to 10% or less.

DCFC charging rates might be a problem if you're pressed for time, but overnight charging with a typical L2 isn't a problem.


I disagree that you'll want to take that much time to charge, as utilities more and more go to ToU rates with restricted hours. SDG&E only has a 6 hour super off-peak window, 12M - 6a.m. I agree that 40A (so that you can use a NEMA 14-50 on a 50A circuit) is reasonable for rental property, or anyone who wants to have the option of portability provided by using a plug-in EVSE. Personally, I'd routinely charge no more than 50-60% (20 or 30% - 80%) and except in extreme circumstances would normally limit myself to 70% max. (20-90%). I've been considering what I'll recommend to my landlord when the time comes, and am thinking that I'd suggest a 60A circuit terminating in a NEMA 14-50 receptacle. That way the occupant can always choose to hardwire it instead for 48A, a simple swap out rather than re-wiring.

Public L2 is a different matter, as those won't need portability, and you want people to be able to get a substantial charge in 2-3 hours (dinner and a movie, say) as well as overnight use.

Restricting to 30-32A or even 40A assumes that packs won't need to continue to grow beyond 100kWh so that they can provide full replacement for fossil-fueled ICEs, and that's extremely unlikely (barring [PH]FCEVs), so 48A or better is what we should aim at. Initially the public ones may be shared some or all the time, but eventually you'll need full power for each EVSE.
 
frontrangeleaf said:
I think it's clear to all but a few of us here (ahem, you know who you are...) that the bump to 7.2kw is a nice and very likely adequate feature improvement. We have a 50 amp service installed in our garage, so we could take advantage of it. I believe some of the other makes are talking about 11kw OBCs, but the real need much above 9 is dubious for home use in my view.

Not that concerned with public infrastructure for reasons I've noted often enough, and that goes doubly for L2 charging.


Sure, 7.2 is an improvement over 3.84, but then pack size has increased by an even greater %, and OBC power is increasing accordingly. With the exception of the Ariya, I know of no other BEV with a 65 or more kWh pack introduced in the past year or two or scheduled to be with a 7.2 kW OBC. They're all at 9.6 kW (base) or more. I'll be interested to see what Hyundai/Kia do when they update the Kona and Niro, as those compete with the Bolt/EUV. Clearly the demand for faster L2 is there, just as it is for faster FC'ing.

Re home use, see my comments about off-peak time windows in my reply to John Locke. If you own a home you can put in whatever circuit you want; those forced to use public L2 who don't have guaranteed parking will need to be able to charge several days of use at a time. We won't have public L2s at every public parking space or private employee lot space for decades and probably never, so each available space needs to be used by multiple cars each week. Faster L2 allows a car to charge less frequently, so more cars can be served by the same charger. It also makes opportunity charging more useful.
 
GRA said:
Sure, 7.2 is an improvement over 3.84, but then pack size has increased by an even greater %
But daily miles driven do not increase proportionally with pack size increase. :eek:

I find it amusing that you trumpet PHEV in one post, and bemoan 7.2 kW in another. Would the real GRA step forward ?
 
GRA said:
johnlocke said:
GRA said:
From March 29th: https://chargedevs.com/newswire/nissan-releases-photos-and-details-of-2022-ariya-electric-suv/


Given the large 90kWh (87kWh usable) pack (and somewhat for the smaller 65kWh, 63 usable) the charging rates seem too low, particularly L2. Everyone else has gone to 40 or 48A OBCs for packs this size, with the Lucid going back to the 80A that Tesla offered on the S way back when, so 30 or maybe 32A before overhead and losses just doesn't cut it any more. It won't fully charge the car in 8 hours.
Unless you hardwire the L2 charger, you're limited to a 50 amp plug. furthermore if you are drawing current for more than 3 hours, you're limited to 40 amps max out of that plug or 9.6 KW. There are plug-in chargers that can do that. Now assuming a100KH battery and 80% discharge (90%-10%), 90% efficiency and 240VAC, you need 9.5 hours to charge back to 90%. If you use a 32A charger instead then you're looking at 11.5 hours. Either way, plug it in when you get home and you'll be charged up in the morning. And who says you have to have a full charge in the morning anyway? Won't 60-70% be enough for the day? And how often are likely to discharge to 10% or less.

DCFC charging rates might be a problem if you're pressed for time, but overnight charging with a typical L2 isn't a problem.


I disagree that you'll want to take that much time to charge, as utilities more and more go to ToU rates with restricted hours. SDG&E only has a 6 hour super off-peak window, 12M - 6a.m. I agree that 40A (so that you can use a NEMA 14-50 on a 50A circuit) is reasonable for rental property, or anyone who wants to have the option of portability provided by using a plug-in EVSE. Personally, I'd routinely charge no more than 50-60% (20 or 30% - 80%) and except in extreme circumstances would normally limit myself to 70% max. (20-90%). I've been considering what I'll recommend to my landlord when the time comes, and am thinking that I'd suggest a 60A circuit terminating in a NEMA 14-50 receptacle. That way the occupant can always choose to hardwire it instead for 48A, a simple swap out rather than re-wiring.

Public L2 is a different matter, as those won't need portability, and you want people to be able to get a substantial charge in 2-3 hours (dinner and a movie, say) as well as overnight use.

Restricting to 30-32A or even 40A assumes that packs won't need to continue to grow beyond 100kWh so that they can provide full replacement for fossil-fueled ICEs, and that's extremely unlikely (barring [PH]FCEVs), so 48A or better is what we should aim at. Initially the public ones may be shared some or all the time, but eventually you'll need full power for each EVSE.
Even if you install 6 gauge wire, you can only pull 40 amps out of a 14-50 plug for more than 3 hours by code. The breaker can't be more than 50A if there's a 14-50 plug. Do you really think the landlord is likely to install larger gauge wire on the premise that someone in the future might want to hardwire a charger? He might let them pay for that improvement if they were lucky. If you are talking about destination chargers, why would you expect them to provide you with more than 40 amps? It's a convenience feature. In 3 hours you could suck down 20 KWH anyway. If your utility limits your lowest cost hours, then you might need to charge on two consecutive nights instead of one. If you need to charge faster than that, DCFC is the answer, not 11KW L2.

As far as batteries being larger than 100KWH in the future, maybe for pickups and delivery vans but not for cars. 300-400 mi range is more than adequate and carrying the extra weight for capacity that you don't use is detrimental to efficiency. Delivery vehicles will have charging stations at their home base capable of charging them at whatever speed the manufacturer deems optimal for their use. Semi's will have DCFC chargers. Pickups will be likely charged overnight for most business use. People who haul trailers will be the oddball case. Likely charging overnight for normal use and DCFC when hauling long distances. People tend to buy pickups for specific needs, so a range of battery sizes and hauling capacities are likely.
 
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