Why shouldn't I charge my 64 kWh Kona EV to 100% every day?

[Wildeyed]

I've got a question which doesn't seem to really be answered in the manual....

I see an option to choose between MAXIMUM/MODERATE/SLOW speed when charging off the 240v .....

considering the fact that I usually charge only once a week (maybe in winter it'll be every 5 days)... and I always do it when I get home from work around 6PM and only leave again around 7AM.... would it be beneficial for the battery life to switch my charging to Moderate? (what is moderate or slow by the way on the 240?)

I think most would agree that when it comes to battery charging slower is better. I'm not sure that drawbacks and benefits are easily quantifiable though there's no shortage of internet pontificating on the subject. Charge as slowly as you can within your charging window and you'll be fine.

 

[persianrider]

Well my friend with his Model 3 LR was charging at the maximum that car could take (he literally had installed 80AMP breakers), I think that car can take 11KW/h of juice

3 year old car, range seemed like it dropped quickly
I told him to charge it slower for 2 cycles and to 100% and see what happens

Now he's literally back to where he should be in terms of range (he was around 440-450 before at 100%, now its showing the 480-490 since he's been charging slower)

So considering that real life knowledge/situation with his car, and the fact that I can allow myself to charge it slow, I think I'll go ahead and do that on Moderate.

I never charge to 100%, always 80%, but in winter I might make it 90%.... we'll see since it'll be our first winter with an EV so its probably more psychological than anything

 

[electriceddy]

I think most would agree that when it comes to battery charging slower is better. I'm not sure that drawbacks and benefits are easily quantifiable though there's no shortage of internet pontificating on the subject. Charge as slowly as you can within your charging window and you'll be fine.

Agreed and also will extend the lifespan of the on board charger.

 

[navguy12]

Well my friend with his Model 3 LR was charging at the maximum that car could take (he literally had installed 80AMP breakers), I think that car can take 11KW/h of juice

3 year old car, range seemed like it dropped quickly
I told him to charge it slower for 2 cycles and to 100% and see what happens

Now he's literally back to where he should be in terms of range (he was around 440-450 before at 100%, now its showing the 480-490 since he's been charging slower)

So considering that real life knowledge/situation with his car, and the fact that I can allow myself to charge it slow, I think I'll go ahead and do that on Moderate.

I never charge to 100%, always 80%, but in winter I might make it 90%.... we'll see since it'll be our first winter with an EV so its probably more psychological than anything

Your friends TM3 didn't lose or gain anything.

The TM3 BMS has a better chance of accurately keeping track of all the energy inputs and outputs if one charges up from, say, 30% to 90% than if one keeps plugging in every night to simply add 10% or 15%.

As for charging at the TM3 on board charger maximum of 11.5 kW (240 volts, 48 amp setting on my wall connector), that is small potatoes compared to the 250 kW that get dumped into a TM3 at a supercharger (obviously 250 kW requires a low SOC and a warm battery).

 

[KiwiME]

... would it be beneficial for the battery life to switch my charging to Moderate?

Aside from the consideration that AC charging at any level accommodated by the Kona's OBC is considered preferable over DCFC (noted in the owner's manual), a likely advantage of keeping it on Max is that the overall efficiency is better. I only charge at 7 amps 230V and fixed OBC overhead losses are sustained for many hours than if I could use a higher rate. I think I get only around 80% into the battery.
At 32 amps I could get as much as 90%.
In any case here is the effect of those settings with my "8 amp" EVSE.

 

[persianrider]

could you explain that in english ? hahaha

the efficiency of what is better ? The car or ?

sorry I reread what you wrote 3 times now and maybe my coffee isn't strong enough but I cant wrap my head around the benefits of charging on the max setting vs effiency

 

[Wildeyed]

could you explain that in english ? hahaha

the efficiency of what is better ? The car or ?

sorry I reread what you wrote 3 times now and maybe my coffee isn't strong enough but I cant wrap my head around the benefits of charging on the max setting vs effiency

Told ya.

 

[persianrider]

that you did! lol

 

[KiwiME]

... would it be beneficial for the battery life to switch my charging to Moderate?

No.

... what is moderate or slow by the way on the 240?

Certainly anything under 7.4 kW and even likely anything under 25kW on DC.

...I cant wrap my head around the benefits of charging on the max setting vs effiency

Charge as fast as you can when on AC for best efficiency. It's sort of like economies of scale ... oh here we go again...!

 

[Esprit1st]

And if you need a little extra juice at home, this might be a solution for you:

 

[David Gagnon]

Hi! I may be able to shed a little light on the "charging to 100% vs. 80%" debate. I work for a energy strorage system design and manufacturing company. We use a slightly different battery chemistry than what you find in EV for infrastructure applications but the principals are very similar.
The reason the BMS doesn't charge to the actual 100% capacity is to avoid battery degradation. When you push the charge to 100% and float it there battery temps tend to rise. Higher temperature cause the electrolytes in the battery to break down. The same phenomenon happens if you drop too close to 0%. We usually have measures built-in to shut down before damaging the battery cells. That's usually what causes thermal run away.
So the main issue with battery life is more about temperature management. The sweet spot for charging is usually between 15°C and 25°C, and 20% to 80% capacity. On my Kona EV Ult, I use the basic level 1 charging, leave it at 90% and try to charge daily and slowly. I'll bring it to 100% if I'm planning a long distance trip, but for daily commutes, weekend runs, 90% to 15% (or around 300 km) is plenty.
If you have any other specific battery questions, feel free to ask!

 

[Ed C]

Why shouldn't you charge to 100% everyday?.....hmmm, to prevent what happened to the Kona EVs in Korea? Cars catching on fire?

 

[janusz Grabon]

Well my friend with his Model 3 LR was charging at the maximum that car could take (he literally had installed 80AMP breakers), I think that car can take 11KW/h of juice

3 year old car, range seemed like it dropped quickly
I told him to charge it slower for 2 cycles and to 100% and see what happens

Now he's literally back to where he should be in terms of range (he was around 440-450 before at 100%, now its showing the 480-490 since he's been charging slower)

So considering that real life knowledge/situation with his car, and the fact that I can allow myself to charge it slow, I think I'll go ahead and do that on Moderate.

I never charge to 100%, always 80%, but in winter I might make it 90%.... we'll see since it'll be our first winter with an EV so its probably more psychological than anything

I own My 2nd Kona EV Ultimate 2020 I did two HV Battery software upgrade and I notice 90% on dash indicate with torque pro is =86% this is reality. On occasion I do charge with my 32A -240V charger to 100% =95.5% also is very slow with very low current .This real !!!!!!

 

[apu]

Why shouldn't you charge to 100% everyday?.....hmmm, to prevent what happened to the Kona EVs in Korea? Cars catching on fire?

I drive to my rural worksites with zero charging infrastructure quite often and in the winter my highway range drops to 280-300km on a full charge, so for myself I have no choice but to charge to 100% 2-4x per week and as Janusz Grabon noticed an indicated 100% charge is not really 100%. Nonetheless I am not really worried about the car blowing up.

I own My 2nd Kona EV Ultimate 2020 I did two HV Battery software upgrade and I notice 90% on dash indicate with torque pro is =86% this is reality. On occasion I do charge with my 32A -240V charger to 100% =95.5% also is very slow with very low current .This real !!!!!!

Yes this is real, nothing unusual here. Your torque pro reading is likely the normally hidden BMS reading of the actual battery SOC.

 

[R P]

I tried to charge to 100% a week or so back, but ran out of time and stopped it at 96% and drawing only 2.3kW (on the dash) at that moment. When I turned on the car and checked the EV charge (on the HU), it read 100%. So that was a little puzzling. It also seemed to be stuck at that 96% for quite a few minutes, so maybe that was really max charge. But like I said, it was still drawing charge. Or maybe it was actually doing some cell balancing. I wish I could have left it a bit longer to see if it would stop charging and/or show 100% at the dash. I didn't have time to do a cell map check with my SoulEVspy, as that would have been interesting, too.

 

[navguy12]

I tried to charge to 100% a week or so back, but ran out of time and stopped it at 96% and drawing only 2.3kW (on the dash) at that moment. When I turned on the car and checked the EV charge (on the HU), it read 100%. So that was a little puzzling. It also seemed to be stuck at that 96% for quite a few minutes, so maybe that was really max charge. But like I said, it was still drawing charge. Or maybe it was actually doing some cell balancing. I wish I could have left it a bit longer to see if it would stop charging and/or show 100% at the dash. I didn't have time to do a cell map check with my SoulEVspy, as that would have been interesting, too.

FWIW: on the rare occasions I need to top up my TM3 to 100%, it will often say 100% but still draw about 1200 watts for about 30 to 40 minutes.

 

[janusz Grabon]

I drive to my rural worksites with zero charging infrastructure quite often and in the winter my highway range drops to 280-300km on a full charge, so for myself I have no choice but to charge to 100% 2-4x per week and as Janusz Grabon noticed an indicated 100% charge is not really 100%. Nonetheless I am not really worried about the car blowing up.



Yes this is real, nothing unusual here. Your torque pro reading is likely the normally hidden BMS reading of the actual battery SOC.

 

[hieronymous]

You are using the wrong SOC pid.
Delete State of Charge BMS, and load the pid State of Charge Display, which shows the same data as the car console...

 

[janusz Grabon]

Thank You I done that. How can I change indoor temp shows in F?

 

[hieronymous]

Thank You I done that. How can I change indoor temp shows in F?

The battery pid you are using is a US conversion, not the original, which shows temps in C, as follows:
000_Battery Module 01 Temperature,Batt Temp01,0x220101,Signed(Q),-40,80,C,7E4
and this is in the .csv file
003_Kona&Niro_EV_BMS.csv

In the .csv file
005_Kona&Niro_EV_Extra_gauges.csv
is this pid for average battery temp:
004_CALC Average Battery Module Temperature,Batt AvgT,0x220101,(val{000_Battery Module 01 Temperature}+val{000_Battery Module 02 Temperature}+val{000_Battery Module 03 Temperature}+val{000_Battery Module 04 Temperature})/4.0,-40,80,C,7E4

Torque Pro has no nice easy way to convert, you need to load the original files, as above.
Otherwise you will need to load your pid file into a plain text editor, and create/add a new pid which converts from F to C, something like:
000_Batt_Temp 01_F2C,Batt Tmp1_C,,(VAL{000_Battery Module 01 Temperature}-32)/9*5,-40,80,C,
then save and reload.
Or you may get lucky when you load your existing pid file into a plain text editor, to find that you can just edit the pid showing F, back to C by deleting the conversion formula details..