Maximizing battery life

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Robert Lewis said:
Understood. However, there was some discussion online (I don't remember where) about the Niro battery being closer to 68-70KWH, with 64 usable. The remaining capacity was reserved such that the battery, even if showing 0% to the driver wasn't actually at 0% state of charge. Similarly, if the driver sees 100% state of charge, the battery wasn't actually charged to 100%. There was that additional capacity reserved at both sides to automatically protect the battery from repeated 100% to 0% to 100% cycles. This is the same thing the Chevy did. In a Gen 2 Volt, the battery's capacity was confirmed to be 16.8KWH, but the usable capacity was limited to about 14.4KWH.

So, it's interesting that Kia would put that in the manual when there seems to be built-in measures to prevent that 100%/0%/100% cycle already, and I don't think any of their warranty language specifies that the owner should follow the 20% to 80% rule to be covered by the warranty.

From personal experience, I charged my 2016 Volt just about every night for 3 1/3 years so far, and experienced zero range/capacity loss in that time. However I had terrible capacity loss in the 2013 Leaf over 3 years I chalk up the difference to the very different approaches to battery management by Chevy and Nissan.
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That's very interesting and is good information about how the battery was handled differently by two different manufacturers. I wouldn't touch a Leaf personally, and just read that their new 62kwh vehicle has a issue of some sort, rapidgate where it slows after getting hot or something?
I wish they(Kia) would clarify if they do have a buffer below 0% and above 100%!
 
There is definitely a buffer above 100%. This becomes obvious when you see that regen is still available even at 100% SOC. I've seen it go as high as 135 kw when pulling the left paddle while traveling at high speed. That regened power has to go somewhere. Most other EVs I've driven had zero regen until the battery level dropped slightly to make room for more charge in the battery.

The size of the buffer is unknown but I'm guessing it's somewhere around 4-5%. The OBD2 sensors show 96.5% BMS SOC for 100% Displayed SOC.

Still, why always charge to 100% if you don't actually need the range? I only drive 45 miles per day and my 100% range is 272. As a result, I typically only charge to 60%. This still leaves me with a large reserve in case I need to make any unexpected trips or can't charge for some reason.
 
My use case is a little different. I'm trying to get by charging only once a week on the Niro, because my wife needs to charge our Volt nightly during the week for her commute, and we only have one level 2 EVSE. So, when I basically get 1 chance a week to charge, I gotta make it count! :)
 
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That makes sense. I could also drive all week on a single charge but luckily have a dedicated charger for the Niro that I can use each night. I guess there's always the included 120V adapter if you don't need to restore more than about 1.1 kw per hour of charge each night.
 
TandM said:
As some others have shared across the web, the L2 charging pattern (power draw) for the Niro differs greatly from that of the Leaf. It's full-on bulk charge until it stops with the Niro, whereas the Leaf trails off and does some rather obvious cell balancing at the end. In the other attachment you can see ours clearly pulled more than 64kW to charge to full, and it was a constant ~7.5kW draw the entire time. I don't think the Leafs, and maybe others, share this same "charge to 100%" recommendation/mentality. They've done a really good thing if their measurements are truly based on a 64kWh "usable" capacity.
Enjoy your new car!
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TandM made another good point above in the other thread regarding the L2 charging rate. The fact that charging rate stays flat up to 100% without tapering like other cars, also suggests that there is a substantial buffer above 100%.
 
Update- we have a 2019 Niro PHEV. We bought it in May 2019.

We now have over 10,000 trouble free miles on the vehicle. If the vehicle is not on the road it is plugged in to charge. We use a L2 station in our garage (Clipper Creek unit). We have charged this in weather over 100 degrees with garage temps approaching 105 degrees. Have experience no problems or range issues. Now that winter is approaching we will be charging it no matter how cool it gets.

That is why we got a Plug In and this routine allows us to maximize savings. Very pleased with this vehicle and its battery management system, battery and hybrid system.

Incidentally I own electric Kobalt mower and weed eater. They both use modular Lithium batteries. I have 5 of these lithium batteries for the yard equipment (They came with the products). They are numbered so I can keep track of them We have owned these tools and batteries for 3 years. The equipment , batteries and chargers are stored in the garage. Last year I accidentally left two batteries on their chargers from November to April with the chargers plugged in. These batteries performed no different than the other three batteries this season.
 
I wish Kia would bring the Niro into the midwest. In talking to local dealers, it sounds like there is no timeline to sell the car here. We gave up waiting and bought a Leaf Plus. Its a great car (I have driven long distances in the height of summer with fast charging without hitting rapid gate, but I know it still is out there), but Kia/Hyundai have a slightly nicer car for a very similar price point. I hope they can ramp up production soon.
 
We also had trouble getting our Niro Plug In. Our local dealer told us no way this vehicle could be gotten in our area.

I was not comfortable with the local dealer from the very start something was just not right with the way they approached us and treated us that made me uncomfortable. They did not listen to our needs and preferences.

On an impulse I used Edmond's New Car buying service where you list the vehicle you want with options you want and Dealers who abide by the service rules bid on your business. A KIA Dealer 60 miles from us had the car we wanted and bid on our business and eventual won it with his low price and customer service. This service was free.

I don't think I'll ever walk into a Dealer again after using this service, unless it is to test drive a vehicle. I was very pleased with the lack of hassle buying a car this way. With the different Dealers bidding against each other we got a great price.

If you haven't done it yet you can go to the KIA website type in the vehicle you want and your zip code and it will show all the Niro's near you. We did receive a bid from a Dealer 500 miles away who offered to ship the car to our house for $350 if we wanted that vehicle.

The Plug ins are a little hard to locate- I thought you might be interested in our experience obtaining one.
 
DougWantsALeaf said:
I wish Kia would bring the Niro into the midwest. In talking to local dealers, it sounds like there is no timeline to sell the car here. We gave up waiting and bought a Leaf Plus. Its a great car (I have driven long distances in the height of summer with fast charging without hitting rapid gate, but I know it still is out there), but Kia/Hyundai have a slightly nicer car for a very similar price point. I hope they can ramp up production soon.
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We didn't want to wait either and so we started getting in touch with dealerships before they were released and picked our Niro EV up in April from a dealership in Maryland and then drove home to Ohio. There are now 4 of the Niro EVs in Central Ohio (and 2 Hyundai Kona) because we were all willing to make a drive to get them (though many of the other folks that have bought since us have had the advantage of looking over our Niro since we frequently take to the EV events and have even met up with a couple people privately so they could get their hands on and get comfortable before committing to a drive to get one).
 
What about service?
My local dealers told me flat out they won’t take the cars for any sort of service. Not even for non-ev items. That seemed like a potential problem point, especially if something incapacitated the car.
 
DougWantsALeaf said:
What about service?
My local dealers told me flat out they won’t take the cars for any sort of service. Not even for non-ev items. That seemed like a potential problem point, especially if something incapacitated the car.
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Mine was in within the first 2 weeks of ownership for a replacement (under extended coverage) of the windshield (including calibration of the cameras which takes special equipment). They took care of it locally with no issues at all. I have since been in for the 7500 mile checkup and they took care of that easily as well. It will be returning to the garage later this week for the SA394 service bulletin and I expect smooth service for that as well. The techs at the local dealership had already been to the hybrid/PHEV/EV training before I purchased my Niro EV and already had serviced a couple Soul EVs (plus they dealership had sold a PHEV which they would be offering service for as well).
 
This spec sheet claims the Niro EV has a 67.1 kWh battery, so about 5%. It does make a significant difference on battery life according to this summary of a study of one kind of cell commonly used in electric vehicles. (The Niro battery chemistry might be a bit different; I have no clue.)

According to the study 0%-70% would buy you the most total energy out of the battery before seeing significant capacity degradation (multiply total cycles by the delta in percentage), though 10%-705 is close behind and 20%-70% is still really good. The difference in life cycle between going to 100% vs. 80% is huge, and going to 70% buys even more. 500 cycles going to 0 to 100% and 1000 going 20% to 100% so about 60% more energy total out of the battery over its life.

This might be splitting hairs though. Working out the total miles before significant degradation assuming 4 mi/kWh, you will get 200k miles going 0 to 100, and since 100% is actually 95% on the Niro you will get probably more like 275k miles. If you are going up to 80% it will be more in the neighborhood of 550k of 600k miles. So maybe it is overkill, but I am a believer in using things as gently as possible within reason so they last a long time. Fewer resources spent making new cars that way. Because of the energy spent making the batteries, electric cars take about 18 months of ownership (20,000 miles maybe?) to reach break even on carbon emissions with a gas power car according to this article . I want my battery running as long as possible.

It is a convenience thing too though, right? I won't hesitate to take it up to 100% (ahem, 95%) for a long trip, and if it is more convenient to drain it to 10% or even 5% instead of 20%, guess what? I figure little variations won't make a big difference as long as I generally shoot for the 80% (75%) down to 10-20% (actually 5%-15%) on my beautiful Niro. Should be good for around 600k miles before it is time to turn the battery into a wall pack.
 
Our car has been plugged in continuously since we bought it in May of 2019. The only time our PHEV is unplugged is if it is being driven or is away from home. After 13,025 miles and 7 months of ownership my impression is that the Kia engineers did a wonderful job on the battery management system and it takes care of the battery charge/discharge cycles fine.

I buy my cars new and put a lot of miles on them. That is why we have them. Our other car is a 2004 Sienna with 149,500 miles on it that I hope to keep 3 more years until it is 20 years old.

I traded a 2008 Prius that we bought new for our 2019 PHEV Niro. Our Prius had over 150,000 miles and as a small car was showing it age on its mechanical parts. That little Prius still got 52 mpg and in its entire life never had one battery or Hybrid system fault. I would be afraid to even attempt a guess on how many charge/discharge cycles that Prius Hybid battery went through in its 12 year-150,000 mile life with us. Its mpg numbers actually improved with age and its battery, hybrid system never faltered once.

If I am going to own a plug in vehicle you can bet I will plug it in every single chance I get and leave it plugged in until it is ready to be driven. That was our whole reason for buying one.
 
With a PHEV with its shorter all electric range, plugging in as much as possible. Nevertheless, you will likely see some capacity loss after 1000 cycles unless they put in HUGE margin. That could take several years though. What is the guarantee for the battery? The full EV battery warrenty, promises 70% capacity 10 years/100k miles
 
The warranty is 10 years or 100,000 miles on the hybrid system.

There is absolutely nothing special about Hybrid or EV vehicles. This technology has been around for decades. The Prius is now approaching its 5th generation. Prius actually get better mileage as they age. Our 2008 Prius was getting 52 mpg when we traded it in and had't had a battery or Hybrid system fault in 12 years and 150,000 miles.

There is comfort in trusting automotive manufacturers and engineers who design cars and leaving the battery management to them and their experience and education!

An example of this is the KIA NIRO is a 5 star Safety+ pick by the NHSTA. I could not have designed a vehicle to meet and exceed these standards nor could I have designed the wonderfully efficiency of the 2019 KIA NIRO PHEV hybrid system
 
John321 said:
The warranty is 10 years or 100,000 miles on the hybrid system. There is absolutely nothing special about Hybrid or EV vehicles. This technology has been around for decades.
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In the 90s, the electric cars were based on lead-acid battery chemistry. The low energy/mass ratio of these batteries meant range was very limited. The Prius uses Nickel metal hydride batteries while most (all?) full EVs use Lithium ion technology of one form or another (higher energy density, lower cycle lifetimes than NiMH) . The Prius Power Control unit that moves energy in and out of battery (think contributing torque to the hybrid power system and harvesting from the wheels and that same system to charge the battery) was completely redesigned about 5 years ago. One reason electric cars did not catch on the 90s outside of niche usage is that the current battery technology limited their utility. Things changed and that is a large reason why they sell OK today.

https://www.just-auto.com/analysis/drilling-down-into-toyotas-latest-hybrid-technology_id171811.aspx
https://en.wikipedia.org/wiki/Toyota_Prius#Design_and_technology

These changes impact power, range and battery life. The fundamental concept of using electricity to drive a motor is still the same, but to say the technology has been around for decades is an oversimplification.
 
Lithium battery technology is even better and more dependable than nickle metal hydride batteries, that is why Toyota has switched to Lithium in the current model Prius. If Nickle metal hydride was the better technology they would have stayed with it.

It is comforting to trust others, especially the ones who design cars and not worry yourself to death or second guess them. It is a rare individual who knows everything there is to know and is more knowledgeable about automotive products and the battery management technologies than the engineers who design them specifically for the cars they market.

I'll just trust the engineers and their abilities. We have a 2004 Sienna that we plan to keep till it is 20 years old and traded in a 2008 Prius that was a wonderful car after 12 years and 150,000 miles. The engineers and their products have done fine by us.

I would expect our Niro to last at least 10 years but I hope 15 years. I certainly won't spend one minute worrying about its technology. People much smarter than I have designed it.
 
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Trades go on in design that are not always driven by what the consumer is interested in.

If I treat my Niro battery gently (like charging from 10 or 20%-70%, taking into consideration the 5% buffer, so around 15-25% taking it up 75%) the battery pack will last with adequate range for a long time, 500k or more miles. If I regularly charge it 0-100%, it won't last more than 200k before capacity is significantly lower. Kia's interest is to sell cars by making them appealing to consumers, not to make them be used as efficiently as possible.

Boeing has a lot of really smart engineers who care about safety, but as that was not the primary guiding principle in getting the 737 MAX out the door (and trying to return to flight ASAP) decisions were made that are counter to what passengers care about.

I will worry about understanding the engineering rather than trust blindly.
 
John321 said:
The warranty is 10 years or 100,000 miles on the hybrid system.

There is absolutely nothing special about Hybrid or EV vehicles. This technology has been around for decades. The Prius is now approaching its 5th generation. Prius actually get better mileage as they age. Our 2008 Prius was getting 52 mpg when we traded it in and had't had a battery or Hybrid system fault in 12 years and 150,000 miles.

There is comfort in trusting automotive manufacturers and engineers who design cars and leaving the battery management to them and their experience and education!
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This is strange thinking by my book, I'm much more in line with David T.

100,000 miles is not high milage at all for a modern car and I would be very unwilling to purchase a used vehicle that only had 70% battery capacity at 100,000 miles. A knowledgable purchaser of our Niro will ask very specifically about what the charging routine of the vehicle was, and expect records, just like oil change records on an antique vehicle.

In 6 years (2025!), an EV with only 170 miles of max range like a heavily degraded Niro is going to be a bad resale value. By then batteries will be 2/3 the cost of current battery packs (well under $100 / kWH storage expected), 300+ mile EVs will be common.

Not seeing degradation of a tiny Prius battery is not a good example of why you should disregard proper charging methods. Prius batteries are supplemental only, they are not the primary propulsion mechanism.

Most importantly, engineers are working under orders from the warranty and marketing departments. A 10 year / 100,000 mile warranty is a sales technique, not an engineering target. Sales does not want normal people to avoid purchasing an EV because it has some mysterious charging routine that is different from what people expect with their phones. "Plug it in and don't worry" is a sales tactic, not an engineering guarantee.

There is so little to go wrong with these vehicles that a cynical person might anticipate that replacing battery packs from hot climate heavy DC / fast charge users will be their only service income stream available in the future.
 
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