[Silent Sam]

I agree, Dr. K. That sounds totally wrong to me too. It's the high powered chargers that can damage batteries; not the low power ones.

 

[coder]

The advice I hear is:
1) rapid dc charging is not good for the battery. It is meant only for times when you are on a tight schedule, and should not be done regularly.

2) It is not good for the battery to spend a lot of time fully charged. It is better to only charge it to 80% ( maybe 90%) so it spends less time in fully charged state.
This is supposed to be a technique that is supposed to help preserving your battery longevity. If you actually need the extra range, top it up to 100% before you need it.
This, again is to minimize the time while the car is sitting these fully charged. The recent battery fire related recall instructions explicitly prompt us do do this.

 

[CocoTheKonaEV]

I just picked up my Kona last week, I texted my salesperson and she said its fine to charge to 100% regularly? In fact she said "Its better to keep at 100% charge."

I still think ill cap it at 80% unless I need the full range...

 

[coder]

Salespeople do not necessarily know the product they sell. You cant go wrong being conservative in this case. If a sales person asserts something that you feel is controversial, you could ask for the source of this information. "what are you basing this recommendation on?" . I would be curious to hear what he says.

 

[Silent Sam]

I just picked up my Kona last week, I texted my salesperson and she said its fine to charge to 100% regularly? In fact she said "Its better to keep at 100% charge."

I still think ill cap it at 80% unless I need the full range...

In my personal experience, as well intentioned as they may be, most Hyundai dealer staff don't seem to know much about EVs. And Hyundai HQ is bafflingly stingy with information. No idea why. Here's what I've managed to dig up off the internet on the subject of charging:

1) Every site related to battery charging that I've visited says that consistent 100% charges can lead to premature battery degrading. That is said to apply to all EV's, not just Konas.

2) Don't try to charge over 80% at a fast (DC) charger. Charging speed drops a lot above 80% and DC chargers (Level III's) in general are said to degrade batteries faster than Level II's (AC chargers). Can't swear if that is true or not, but intuitively I'd suspect it is. Level II units charge at a leisurely 7.2 -- 7.4 Kwh. Level III's slam the charge rate up to 30 -- 50 Kwh.

3) When using an AC (Level II, or home style) charger, limit to 80 -- 90% charge. If you are travelling a distance -- such as out of town -- it's OK to charge to 100%, but only do it on a Level II (AC) charger. One site suggested that for speedier 100% charges, do the first 80% on a Level III (DC) charger and then top off to 100% on a Level II. Sounded reasonable.

4) Another site I visited recommended running batteries down to 30 -- 50% before recharging. It seems reasonable too. As I've installed a Level II charger at home, that is another charging protocol I've adopted for my Kona EV. So far it seems to be working fine.

5) Just as a FYI...where I live electricity is hydro generated and costs about 10.5 cents per Kwh. Depending on driving conditions, that translates to between 1.5 -- 2.0 cents per kilometre. The VW Golf I had before my EV was pretty economical as internal combustion vehicles go. But at the present price for gasoline where I live ($1.22/litre) it would cost around 10.5 cents per kilometre to drive the VW, or at least five times as much as the EV. One more reason to love your electric car...

 

[Mechanic]

I'm a mechanic at Hyundai and also working with the kona ev. If the HV battery is charged at 100% this is at 4.2v per cell. This is the maximum capacity for this type of battery (Lithium-ion polymer). 4.2v is 100%. not 80% charge.

Like a cellphone battery charging to 100% all the time would shorten the lifespan of the battery pack to 300/500 charging cycles, but due to better temperature regulation this can be longer, in the link below it is explained.
Source: How to Prolong Lithium-based Batteries - Battery University

 

[MSimpsonNJ]

I'm a mechanic at Hyundai and also working with the kona ev. If the HV battery is charged at 100% this is at 4.2v per cell. This is the maximum capacity for this type of battery (Lithium-ion polymer). 4.2v is 100%. not 80% charge.
View attachment 5030

Like a cellphone battery charging to 100% all the time would shorten the lifespan of the battery pack to 300/500 charging cycles, but due to better temperature regulation this can be longer, in the link below it is explained.
Source: How to Prolong Lithium-based Batteries - Battery University

I just picked up my brand new 2020 Kona EV yesterday and as it is my first EV I'm trying to discover all the nuances as quickly as I can (and will get my baptism by fire next week as I am taking a 1200 mile trip to Florida!)

I see a lot about the 80%-max-except-when-doing-long-distance-between-stops rule and plan on keeping to this rule as best I can. I see a little discussion about the low limit but not as much. Not that I want to get to this point, but what are the downsides to going below say 20%, and how low can you go without doing real damage?

Thanks for all of the above information.

 

[Silent Sam]

I just picked up my brand new 2020 Kona EV yesterday and as it is my first EV I'm trying to discover all the nuances as quickly as I can (and will get my baptism by fire next week as I am taking a 1200 mile trip to Florida!)

I see a lot about the 80%-max-except-when-doing-long-distance-between-stops rule and plan on keeping to this rule as best I can. I see a little discussion about the low limit but not as much. Not that I want to get to this point, but what are the downsides to going below say 20%, and how low can you go without doing real damage?

Thanks for all of the above information.

I can think of two downsides. First is, the lower you run your reserve before planned refuelling, the more you risk running out entirely. For instance, suppose you schedule a charge stop when you expect to be down to say, 20%. You arrive at the the rechargers and find they aren't working. Judging from some reviews I've seen on YouTube, that does apparently happen, though I've never experienced it myself and sure don't want to. Regardless, if it does, you will have very limited reserve available to get you to another charger.

How low can you run your batteries? My understanding is, once you approach zero reserve, it can apparently damage them. Can't swear that's so, but I have read on a related website that full discharge can harm lithium batteries.

We've had a 2021 Kona EV for about six months. We've made a few road trips with it. Our protocol is to charge to 100% on our level-2 charger before leaving home. Then we schedule a a charging stop at somewhere between 30% and 50% reserve. So far that's worked out OK for us. And it leaves enough wiggle-room to look for an alternative one if for any reason we can't access the intended charger.

And an observation: we live in British Columbia and when we first got our EV we were pretty paranoid about road trips. There are numerous level-3 public chargers (both government and commercial) being installed across the province, but there are still some sizeable sketchy areas. However, we've found if you do a bit of planning before leaving home, things work out OK. But it sure is different than travelling by conventional vehicle.

Not that I'm complaining. When I see fossil fuel prices take a sudden and arbitrary jump of almost 20% as they did recently where I live, I smile, drive home and plug into my personal level-2 charger. I know for sure I'll be paying $0.10/Kwh for my fuel and that works out to around $0.02/km (approx. $0.03/mile), or less. If I still had my VW Golf (a pretty economical car by fossil fuel standards) I'd be paying $0.10/km ($0.16/mile) and more.

Have a great trip, BTW. I'm sure you'll find more than enough charge points to keep you comfortably motoring. And you are going to love driving your new EV...

PS: If you haven't already downloaded Plug Share <PlugShare - Find Electric Vehicle Charging Locations Near You> give it a try. It can be quite helpful.

 

[Kiwi]

I see a lot about the 80%-max-except-when-doing-long-distance-between-stops rule and plan on keeping to this rule as best I can. I see a little discussion about the low limit but not as much. Not that I want to get to this point, but what are the downsides to going below say 20%, and how low can you go without doing real damage

Some new owners get confused between 80% being a practical fast-charging level (because the charge rate drops and cost/kWh may increase, or the charger stops automatically before 100%) and being kind to the battery by limiting charge to levels under 100% on a daily-driving basis. On a trip, best ignore the latter and charge as much as you feel you need in order to safely reach your next planned waypoint.

As for going under 20%, the general advice is to charge to above 20% as soon afterwards as is practical. In any case charging after driving while the battery is still warm is generally a good plan because charging speed is best when the pack is at 25°C or over.

 

[engnrng]

There is information in the manual from Hyundai that recommends charging settings. If I did not live on the top of a hill, I would charge to 100% every 3 or 4 days. Instead I set at 90% for my home level 2 charging so that I gain a couple of miles of range on the way down the hill.