WetEV
Posts: 2069
Joined: Fri May 04, 2012 8:25 am
Delivery Date: 16 Feb 2014
Location: Near Seattle, WA

Re: Possible Widespread 2018 Traction Battery Quick Charge Problems

Wed May 02, 2018 8:29 am

SageBrush wrote:
arnis wrote: going to SuperCharger after battery has been cold soaked might mean an hour of idling just to get the pack warm enough to take ANY charge..

BS


https://teslamotorsclub.com/tmc/threads ... ed.105897/

Read and weep.
WetEV
#49
Most everything around here is wet during the rainy season. And the rainy season is long.
2012 Leaf SL Red (Totaled)
2014 Leaf SL Red

Oils4AsphaultOnly
Gold Member
Posts: 395
Joined: Sat Oct 10, 2015 4:09 pm
Delivery Date: 20 Nov 2016
Leaf Number: 313890
Location: Arcadia, CA

Re: Possible Widespread 2018 Traction Battery Quick Charge Problems

Wed May 02, 2018 8:50 am

arnis wrote:
WetEV wrote:Would be useful for really cold places, as the battery heater wouldn't use as much power due to insulation. Think Yukon. Places where the battery heater is on nearly all the time, trying hard to keep the pack above 0C.

Worse than useless for me.


True. Most fans don't even know that, but Tesla's pack is far from perfect. In my climate,
it's also "worse than useless". My Leaf has battery below -5*C for two months. Heating it up every day is nonsense.
Nissan's chemistry can regen and DC charge even at -5*C. That is not possible on Tesla's.
Note, Model 3 doesn't have dedicated battery heater and going to SuperCharger after battery has been cold soaked might mean an hour of idling just to get the pack warm enough to take ANY charge. Unheardof and worse than useless.


If it's -5C outside, and the Tesla's cold-soaked, I'm going to preheat my Tesla, and wouldn't you know it, that's exactly what's needed to warm up the battery to enable supercharging. And the model 3 (via software) uses its inverter as the battery heater. Nice red herring though.
:: Model 3 LR :: acquired 9 May '18
:: Leaf S30 :: build date: Sep '16 :: purchased: Nov '16
Date - Miles / GIDs:
May '17 - 7300 mi / 363
Feb '18 - 20.5k mi / 333
... awaiting firmware update

lorenfb
Posts: 1760
Joined: Tue Dec 17, 2013 10:53 pm
Delivery Date: 22 Nov 2013
Leaf Number: 416635
Location: SoCal

Re: Possible Widespread 2018 Traction Battery Quick Charge Problems

Wed May 02, 2018 9:13 am

Oils4AsphaultOnly wrote: And the model 3 (via software) uses its inverter as the battery heater.


You're implying that drawing battery current by loading the motor, e.g. brakes on, and generating battery heat (internal resistance),
is what occurs, right? The inverter is very efficient, i.e. 95-98%. Or did I miss something?
Leaf SL MY 9/13: 65K miles, 50 Ahrs, 5.2 miles/kWh (average), L2 charges to 100% > 1000, max battery temp < 95F, min discharge point > 20 Ahrs

Oils4AsphaultOnly
Gold Member
Posts: 395
Joined: Sat Oct 10, 2015 4:09 pm
Delivery Date: 20 Nov 2016
Leaf Number: 313890
Location: Arcadia, CA

Re: Possible Widespread 2018 Traction Battery Quick Charge Problems

Wed May 02, 2018 9:39 am

lorenfb wrote:
Oils4AsphaultOnly wrote: And the model 3 (via software) uses its inverter as the battery heater.


You're implying that drawing battery current by loading the motor, e.g. brakes on, and generating battery heat (internal resistance),
is what occurs, right? The inverter is very efficient, i.e. 95-98%. Or did I miss something?


indeed the inverter is very efficient, but 2-5% loss of 100kw ( 192kw motor max draw, so reducing that for cold battery draw) still provides 2-5kw (edit: bad math earlier) of waste heat from the inverter. Add in the internal battery resistance and it adds up to more than chump change.
:: Model 3 LR :: acquired 9 May '18
:: Leaf S30 :: build date: Sep '16 :: purchased: Nov '16
Date - Miles / GIDs:
May '17 - 7300 mi / 363
Feb '18 - 20.5k mi / 333
... awaiting firmware update

Oils4AsphaultOnly
Gold Member
Posts: 395
Joined: Sat Oct 10, 2015 4:09 pm
Delivery Date: 20 Nov 2016
Leaf Number: 313890
Location: Arcadia, CA

Re: Possible Widespread 2018 Traction Battery Quick Charge Problems

Wed May 02, 2018 9:43 am

lorenfb wrote:
Oils4AsphaultOnly wrote: And the model 3 (via software) uses its inverter as the battery heater.


You're implying that drawing battery current by loading the motor, e.g. brakes on, and generating battery heat (internal resistance),
is what occurs, right? The inverter is very efficient, i.e. 95-98%. Or did I miss something?


Oh, and the full drivetrain losses (battery, power electronics, inverter, and motor) is ~11%+
https://model3ownersclub.com/threads/mo ... el-s.5252/

So you could scavenge 10kw of heat from that.
:: Model 3 LR :: acquired 9 May '18
:: Leaf S30 :: build date: Sep '16 :: purchased: Nov '16
Date - Miles / GIDs:
May '17 - 7300 mi / 363
Feb '18 - 20.5k mi / 333
... awaiting firmware update

User avatar
RegGuheert
Posts: 6208
Joined: Mon Mar 19, 2012 4:12 am
Delivery Date: 16 Mar 2012
Leaf Number: 5926
Location: Northern VA

Re: Possible Widespread 2018 Traction Battery Quick Charge Problems

Wed May 02, 2018 12:34 pm

Here is a review by a 2018 LEAF owner who disagrees with the premise of this thread:
Gary Lieber at InsideEVs wrote:The rumors about the new Leaf not being able to endure multiple DCQC without excessive charge time slowdowns proved to be unfounded. During the trip, charging behaviors were no different from previous 2011 and 2014 Leafs. The most significant challenge is that a larger battery can mean longer charge times regardless of the charge rate. All BEVs throttle their charge rates as the battery fills up, but the 2018 Leaf’s charge profile does not seem any different from earlier generations. The challenge for all BEVs is that the larger the battery, the longer time it will take. As infrastructure and BEV charge rates increase, charging times will improve, but the laws of physics apply and the bigger the battery, the longer it will always take.
RegGuheert
2011 Leaf SL Demo vehicle
10K miles: Apr 14, 2013, 20K miles (55.7Ah): Aug 7, 2014, 30K miles (52.0Ah): Dec 30, 2015, 40K miles (49.8Ah): Feb 8, 2017, 50K miles (47.2Ah): Dec 7, 2017.
Enphase Inverter Measured MTBF: M190, M215, M250, S280

lorenfb
Posts: 1760
Joined: Tue Dec 17, 2013 10:53 pm
Delivery Date: 22 Nov 2013
Leaf Number: 416635
Location: SoCal

Re: Possible Widespread 2018 Traction Battery Quick Charge Problems

Wed May 02, 2018 12:46 pm

Oils4AsphaultOnly wrote:
lorenfb wrote:
Oils4AsphaultOnly wrote: And the model 3 (via software) uses its inverter as the battery heater.


You're implying that drawing battery current by loading the motor, e.g. brakes on, and generating battery heat (internal resistance),
is what occurs, right? The inverter is very efficient, i.e. 95-98%. Or did I miss something?


Oh, and the full drivetrain losses (battery, power electronics, inverter, and motor) is ~11%+
https://model3ownersclub.com/threads/mo ... el-s.5252/

So you could scavenge 10kw of heat from that.


Unless the power electronics (includes the inverter) and the motor are "tightly integrated" physically with the battery, I doubt that they
transfer much heat to the battery. All the heat generation to battery results from the battery's internal losses (resistance).

Note: The MS with the 18650s has about the same battery resistance as the Leaf (~ 56 mohms). Use of the later 2170 cell in the M3 battery
most likely results in a different resistance (probably lower).
Leaf SL MY 9/13: 65K miles, 50 Ahrs, 5.2 miles/kWh (average), L2 charges to 100% > 1000, max battery temp < 95F, min discharge point > 20 Ahrs

Oils4AsphaultOnly
Gold Member
Posts: 395
Joined: Sat Oct 10, 2015 4:09 pm
Delivery Date: 20 Nov 2016
Leaf Number: 313890
Location: Arcadia, CA

Re: Possible Widespread 2018 Traction Battery Quick Charge Problems

Wed May 02, 2018 1:00 pm

lorenfb wrote:
Oils4AsphaultOnly wrote:
lorenfb wrote:
You're implying that drawing battery current by loading the motor, e.g. brakes on, and generating battery heat (internal resistance),
is what occurs, right? The inverter is very efficient, i.e. 95-98%. Or did I miss something?


Oh, and the full drivetrain losses (battery, power electronics, inverter, and motor) is ~11%+
https://model3ownersclub.com/threads/mo ... el-s.5252/

So you could scavenge 10kw of heat from that.


Unless the power electronics (includes the inverter) and the motor are "tightly integrated" physically with the battery, I doubt that they
transfer much heat to the battery. All the heat generation to battery results from the battery's internal losses (resistance).

Note: The MS with the 18650s has about the same battery resistance as the Leaf (~ 56 mohms). Use of the later 2170 cell in the M3 battery
most likely results in a different resistance (probably lower).


I don't have a reference handy, but I believe the coolant is shared between all the components of the power-train. Anyway, it's non-trivial amount of heat.

Besides, no one has proven that the model 3 can't work in cold weather yet (the earlier link was about supercharging while cold, not any pre-conditioning that's available to the user), so saying that it can't run in -5C is just speculation at best, FUD at worst. We jump through many hurdles to make the leaf work for our daily lives (timing the full charge to when we leave, not discharging below 20% and leaving it parked, not parking it outdoors under the sun when it's hot outside, etc), so it's just a matter of figuring out what the idiosyncrasies of the model 3 are.
:: Model 3 LR :: acquired 9 May '18
:: Leaf S30 :: build date: Sep '16 :: purchased: Nov '16
Date - Miles / GIDs:
May '17 - 7300 mi / 363
Feb '18 - 20.5k mi / 333
... awaiting firmware update

alozzy
Posts: 986
Joined: Fri Jan 20, 2017 4:25 pm
Delivery Date: 18 Jan 2017
Location: Vancouver, BC
Contact: Website

Re: Possible Widespread 2018 Traction Battery Quick Charge Problems

Wed May 02, 2018 1:58 pm

Can you guys start a new thread? I'm getting tired, looking at this one for new updates on #rapidgate, only to find posts about unrelated stuff...
Vancouver, CA owner of a 2013 Ocean Blue SV + QC, purchased 01/2017 in WA
Zencar 12/20/24/30A L1/L2 portable EVSE
1-1/4" Curt #11396 hitch
After market, DIY LED DRLs
LeafSpy Pro + Konnwei KW902 ELM327 BT OBDII dongle
Loving my first BEV :D

arnis
Posts: 873
Joined: Sat Jan 23, 2016 3:21 pm
Delivery Date: 23 Jul 2014
Leaf Number: 015896
Location: Estonia, Europe

Re: Possible Widespread 2018 Traction Battery Quick Charge Problems

Wed May 02, 2018 2:10 pm

Well, AFAIK, Model 3 needs an hour to preheat the battery. I heat no more than 5 minutes.
This is far from enough for Model 3. Also I don't have that much grid power available to have two 6kW heaters blasting
on Model S/X. Battery will drain. Also going back home, car is not plugged in after work day.
Also, energy is not free, even from the grid. Like I said, heating battery like Tesla and Bolt is not reasonable.
I agree that for SuperCharging, battery should be warmed up. But not for 40kW regen.

This is not total offtopic. It's something similar as with Leaf2. Leaf2 battery gets hot too easily, Tesla/Bolt battery gets
cold too easily. I'd rather have reduced charge rate than no charging/regen at all.
Short range EVs <30kWh -- Medium range: 30-60kWh -- Long range: >60kWh
Charging: Trickle <3kW -- Normal 3-22kW -- Fast 50-100kW -- Supercharging >100kW

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