Underwhelming cold weather performance

[SmartElectric]

Having owned a 2013 Smart ED and now a 2017 Smart ED, they both do 30kW (ie maximum) regen until about -15C when it's slightly reduced to 15kW regen. Very different battery chemistry to Tesla, and is a fully heated/cooled battery pack as well. Pretty good tech for a small runabout.


Our 2013 Tesla S85 is the classic original "A" battery pack with maximum 88kW supercharging and suffers as everyone else reports from reduced regen and supercharging in cold weather. My solution is to charge to 100% for long road trips (we routinely charge to 100 most every weekend in winter for this reason) and 30 minutes pre-heat before driving. Also use the trick Bjorn Nyland vlogged about to accelerate and regen repeatedly to warm battery when you are nearing a supercharging stop to heat up the battery, using this method I routinely top out maximum supercharging even in the coldest conditions.

 

[Lon12]

Just wish we had access to the battery temperature somewhere. At -15C I can have full regen showing (solid line no dots) but still only get half the power from the supercharger. So I don't know if I need to warm up the pack more using Bjorn's method.

 

[Ledge]

Agreed. I think there is likely something the tesla engineers know about their battery performance and there are likely valid reasons why they made these design choices. It's just very different from what I am 'used to' and tesla is far ahead in so many other aspects relative to other EVs, this one just kind of stands out to me.

As others have said, Tesla goes out of it's way to protect the battery, which seems to work as the average battery degradation on Tesla batteries seems to be around 3-7% after 100,000km.

On the other had, a couple of co-workers with other EVs have seen battery degredation of 15-30% after 100,000km.

Yes, Tesla could allow you full regen and charging on a cold battery, but that comes at a high cost. Other EVs suffer from the same issue, however the other manufacturers either don't care, or like the prospect of selling replacement batteries in cold climates.

 

[pcons]

As others have said, Tesla goes out of it's way to protect the battery, which seems to work as the average battery degradation on Tesla batteries seems to be around 3-7% after 100,000km.

On the other had, a couple of co-workers with other EVs have seen battery degredation of 15-30% after 100,000km.

Yes, Tesla could allow you full regen and charging on a cold battery, but that comes at a high cost. Other EVs suffer from the same issue, however the other manufacturers either don't care, or like the prospect of selling replacement batteries in cold climates.

That's a fair point. The only thing I could counter that with is that GMs also don't have any noticable degradation yet allow regen. I know leafs and kias have had big problems with degradation.

However, I had about 50,000 km on each of my volts before I sold them and literary had the same range as new on both. Not 7%, zero range loss. There are many other examples on the Volt forums with similar experiences. Now my wife's bolt is only 1.5 years old, but I expect the same from that as well.

I get the battery chemistry may be different, but my original point was tesla is so far ahead of others in many respects, but not this one. I agree it's likely they are playing it conservative to mitigate risk of losing a lot of money replacing batteries, but they take lots of risks elsewhere.

 

[Ledge]

That's a fair point. The only thing I could counter that with is that GMs also don't have any noticable degradation yet allow regen. I know leafs and kias have had big problems with degradation.

However, I had about 50,000 km on each of my volts before I sold them and literary had the same range as new on both. Not 7%, zero range loss. There are many other examples on the Volt forums with similar experiences. Now my wife's bolt is only 1.5 years old, but I expect the same from that as well.

I get the battery chemistry may be different, but my original point was tesla is so far ahead of others in many respects, but not this one. I agree it's likely they are playing it conservative to mitigate risk of losing a lot of money replacing batteries, but they take lots of risks elsewhere.

Interesting, I did not realize the volt/bolt had such little degradation. Would be interesting to know why their batteries can last so much better.

 

[Uncle Paul]

On colder mornings I often will charge up for about 15 minutes prior to heading out. Seems to warm up the battery enough to avoid that heavy draw for the first miles.

 

[H2050]

In Canada we are getting 10 below freezing all day.
My trip from work to home has 0 regen the whole trip.
My trip to work is better because i start from garage and plugged in.

But I'm sure in the future we will get OTA update to warm battery for cold weather more easily.
For now I'll just burn some breaks on a few cold days.

 

[bijan]

That's a fair point. The only thing I could counter that with is that GMs also don't have any noticable degradation yet allow regen. I know leafs and kias have had big problems with degradation.

However, I had about 50,000 km on each of my volts before I sold them and literary had the same range as new on both. Not 7%, zero range loss. There are many other examples on the Volt forums with similar experiences. Now my wife's bolt is only 1.5 years old, but I expect the same from that as well.

I get the battery chemistry may be different, but my original point was tesla is so far ahead of others in many respects, but not this one. I agree it's likely they are playing it conservative to mitigate risk of losing a lot of money replacing batteries, but they take lots of risks elsewhere.

How do you measure battery degradation on the volt/bolt? Is this rated range or guesstimated range?

 

[StealthP3D]

It's incredibly wasteful to warm the battery simply to increase regen. You will never recover the energy used to heat the battery by regen braking.

 

[mswlogo]

Same here. Physics sucks, takes a lot of energy to heat up the interior space by ~ 20-30C.

Because my wife mainly drives to the go train and commutes downtown her range loss is insane, because she basically heats the car for a 10 min commute, then all that energy that went into heating is lost while it sits all day. Then it repeats at night when she returns. ITs something we are used to, but it is a little crazy when her bolt, which gets ~ 410km to a charge in the summer, is now getting about 180/charge in the winter

I do wish tesla would show a breakdown of what % went into cabin heating vs propulsion like on the volt/bolt. It really trained me to be a bit more frugal with the heat. Just like how driving 100 km/h vs 120 km/h makes a big difference; setting the interior heat to 19-20C vs 22-23C also matters a lot.

It would be nice if the wh/mi was split into propulsion and heat wouldn't it.
You can generally figure it out though.

Just turn heat OFF for a few minutes and watch your wh/mi or energy chart.
In your wifes short commute to the train it's probably using 100 wh/mi or more.

It was in in the was about 28F today and low teens last night. Nice and sunny, so for grins I left heat off today while I ran a few errands.
It pretty much hit EPA spec 250 wh/mi. That was with pretty much no regeneration driving around town.

 

[mswlogo]

It's incredibly wasteful to warm the battery simply to increase regen. You will never recover the energy used to heat the battery by regen braking.

Yeah some people are really hung up on regen and they will pay more to get it than it saves.

I pre-heat my cabin for about a whole 2 minutes. I decide I'm leaving, I turn the cabin heat on, by the time I reach the car it's comfy.
It was like 28F in the cabin when I turned it on. It was 66F when I reached the car. My work building is small (20 employees) and my car is parked adjacent to the building.

 

[SmartElectric]

How do you measure battery degradation on the volt/bolt? Is this rated range or guesstimated range?

My 2013 Smart ED had a NMC battery pack with liquid temperature conditioning.
When measured on the Daimler maintenance schedule, the Ah rating came back 99% original capacity after 4 years and 30000 km.

Again, lots of regen in the cold and always charged to 100% nightly for 1200 straight days. While it was a small 17.6kWh pack, it was outstanding in terms of it's behaviour and usefulness in all weather conditions.

Tesla has a different cell chemistry and chooses to disable regen in temperature ranges that other EV’s can allow regen. It’s a fact.

 

[Lon12]

I don't get any cold weather regen in the Leaf.

 

[mociaf9]

It's incredibly wasteful to warm the battery simply to increase regen. You will never recover the energy used to heat the battery by regen braking.

If you're wanting regen for energy savings....yeah, that's usually going to be a net waste. However, for those who are interested in maximizing the range they're able to drive as opposed to minimizing their total net electricity consumption, it's an advantage. Also if you're doing it so that the car's driving behavior is always roughly consistent--this makes driving safer--then a net energy loss isn't really relevant. Or, if you are starting your drive with a decent downgrade distance, pre-spending the electricity to warm up the battery enough to enable regen could actually be a net positive for total consumption. All these things are context and circumstance dependent.

 

[StealthP3D]

Tesla has a different cell chemistry and chooses to disable regen in temperature ranges that other EV’s can allow regen. It’s a fact.

Overall, the Model 3 is still more efficient than other EV's. And Tesla doesn't "disable" regen unless the battery pack becomes extremely cold or the battery is already charged 100%. In cold weather, it's normal to have somewhat reduced regen but typically there is still enough for normal driving without using the friction brakes except for a light touch when you need to come to a complete stop. So I don't see reduced regen in cold weather as being the big deal that a few people try to make it out to be.

 

[Drone Flyer]

Out of all the many many things I love about my model 3, the choices made on Regen in cold weather still confuse me relative to all the other EVs I've owned.

Aside from the tire related Regen reduction which is well documented: my car basically always has over half the Regen bar full of dots because I don't have workplace charging and because I don't plug in every night. This makes it more convenient to summon the car out if the garage in the morning, and with such a large battery I only charge every 3-4 days when I get down to 100km of range or so.

But here's what prompted this post:

Today it was -8C, and when I got into the car there was literally zero Regen at all speeds because it was all dots on the Regen bar. It was like that for over 1/2 of my commute. I've never lost Regen so dramatically on my other EVs due to temperatures and it's really one thing I wish tesla would address. But it does seem like this is the way they have always been.

Maybe it's because their batteries can't take it, but I find that hard to believe since my wife's bolt can still Regen up to 60 kW in the dead of winter after sitting parked for 3 days.

Also, even though Regen was so limited, the full battery was available. Yesterday it was warmer, I didn't lose full Regen, and yet when I got into the car I had the blue snowflake icon which didn't go away until the end of my drive. Today it was colder, lost all Regen, but no battery snowflake.

Tesla does so many things better than others, butbthis Regen behaviour is really annoying. I'll basically be using brakes for over 1/2 of my winter driving at this rate.

Sounds like you are charging 100 percent! Never charge to 100 percent unless you are going
Immediately on a long trip away from Superchargers. Charging to 100 percent decreases the life of the battery if used all the time! Surprised Tesla didn’t tell you that. Charge to 90 percent everyday and you will have plenty of regen. And yes, charge everyday, try not to leave it unplugged at night.

 

[Drone Flyer]

In Canada we are getting 10 below freezing all day.
My trip from work to home has 0 regen the whole trip.
My trip to work is better because i start from garage and plugged in.

But I'm sure in the future we will get OTA update to warm battery for cold weather more easily.
For now I'll just burn some breaks on a few cold days.

“In Canada we are getting -10 everyday”? Not true.!
In Vancouver and Victoria it is about plus 10 C everyday.
Not everyone lives in cold climates in Canada you know! Lol!

 

[Darthbenji]

If you're wanting regen for energy savings....yeah, that's usually going to be a net waste. However, for those who are interested in maximizing the range they're able to drive as opposed to minimizing their total net electricity consumption, it's an advantage. Also if you're doing it so that the car's driving behavior is always roughly consistent--this makes driving safer--then a net energy loss isn't really relevant. Or, if you are starting your drive with a decent downgrade distance, pre-spending the electricity to warm up the battery enough to enable regen could actually be a net positive for total consumption. All these things are context and circumstance dependent.

Don’t forget wanting regen to avoid wear on brakes and expensive brake jobs at Tesla.

 

[Funkmobile]

Don’t forget wanting regen to avoid wear on brakes and expensive brake jobs at Tesla.

Someone should fully cost out how "wasteful" preheating your battery is. Something on the lines of, you spend X amount of electricity preheating, but you gain Y amount back from increased regen. The difference is how much is "wasted" and measure that against the environmental cost of producing extra brake pads, rotors, and service costs

 

[SmartElectric]

Overall, the Model 3 is still more efficient than other EV's.....I don't see reduced regen in cold weather as being the big deal that a few people try to make it out to be.

True. Our huge Tesla S is every bit as efficient as my little Smart. But the Smart has more consistent regen, which is nice, if not a big deal.