Lawrence Ziehr, the Ultium Power Restoration Mission Supervisor for Basic Motors not too long ago led his group on a freezing-cold subject journey to Sault Ste. Marie on Michigan’s Higher Peninsula. The journey not solely put the group’s merchandise to the take a look at, as their battery-electric take a look at automobiles needed to perform within the chilly, however it additionally uncovered the engineers to the real-world challenges confronted usually by clients.
We chatted with Ziehr to listen to concerning the group’s experiences and classes discovered on the journey.
Q: What took your group to Sault Ste. Marie?
Lawrence Ziehr: We’re actually making an attempt to grasp real-world use instances that our clients should expertise each day. We attempt to put ourselves instead of that. There’s loads we will do in testing and chilly chambers, and we do plenty of that. We do quick charging and now we have wind tunnels and so forth and we will simulate snow however there’s simply no substitute for precise in-use [experience].
Q: And what did you discover on the market in the true world?
Lawrence Ziehr: In one of many examples we obtained to a church [charging] station, and it was useless. That is not an issue we examined in our chamber. However these are buyer real-world [problems]. We obtained to a cost station with 37 miles of vary. And we’re like, “The place can we go from right here?” You need to have a backup. There is a plan that you just’ve obtained to have.
The [thermal management] system that I am answerable for is definitely an enormous enabler to at the very least assist clients with that anxiousness as a result of it is making an attempt to avoid wasting and preserve power in these situations. These had been issues that we had been truly capable of expertise, and it was like if we did not have our methods on board, we would not have made it [to the destination].
I am like, “I am unable to consider we’re truly experiencing this like this,” as a result of it actually is definitely making use of expertise in use. It is laborious to get that within the tunnel, however truly getting out within the subject and seeing that and, and actually understanding how issues change and you’ve got to have the ability to accommodate however actually having the expertise that contributes in direction of effectivity permits automobiles to go farther in chilly.
Q: How a lot charging did you do in these in these chilly temperatures and what impact did you discover that having the charging time
Lawrence Ziehr: We in all probability fast-charged about six occasions within the chilly. And we did some with preconditioning, and a few with out preconditioning, and it is an enormous distinction. That is one thing that I believe is actually an schooling piece. That is manner totally different than your [internal combustion engine vehicle]. You do not have to fret about preconditioning, you are driving to the gasoline station, you simply have to fret about attending to a gasoline station that has gradual pumps, however that is very uncommon.
However preconditioning is an enormous deal. On this instance, we had been driving up, and this was our first cease, we had been all into the entire journey and we fully forgot to precondition the automobiles for our first cease. Plenty of issues occurring. However we obtained there and most of the people’s expertise precisely, it took us twice as lengthy to quick cost.
Q: What’s “Twice as lengthy”?
Lawrence Ziehr: It is like an hour and a half. We solely deliberate for 45 minutes. And that put us behind. We had a timeframe that we needed to be up there. However we had been now behind as a result of we had forgotten one thing so simple as one thing that we preach to our clients and we stated, “Oh yeah.” That is actually placing in an instance that our clients will expertise. It was “I need to go quick cost and my time was double what I anticipated.”
When you need to do preconditioning is actually, I believe, the underside line. We have to get educated by way of understanding what that’s and the advantages of it. You probably have a route plan, we’ll routinely precondition and it simply does it. We did have route plans, however we did not set it up as a result of we had been behind and we knew the place we had been going.
You probably have a route plan, it is going to do it routinely. Or you may invoke it. You possibly can undergo the display screen and really flip it on by the car. You may also entry it by the app. In plenty of our [test] automobiles, we do not have the app connections as a result of they don’t seem to be manufacturing automobiles, they’re improvement automobiles. We have a tendency to not have the flowery app stuff, so we’re accessing it extra manually by the automobile. With out the route plan in there, we obtained to the church station, it was like “Nope.”
Q: So that you corrected that mistake for subsequent charging stops?
Lawrence Ziehr: After that, it was noticeably totally different. No joke, pull in, quick cost! The Cadillac Lyriq, I believe we had been hitting 140-something kilowatts. It was no joke: half an hour, that automobile was able to go! So it was extraordinarily constructive by way of like an expertise of what our clients would truly be.
The Cadillac ELR hybrid-electric car present process cold-weather testing on Michigan’s Higher Penninsula in earlier winter testing.
Q: What number of ranges of the menu do you need to undergo to get to the precondition button?
Lawrence Ziehr: Two. That is an excellent query. I am glad you introduced that up as a result of I believed that was one thing that is likely to be one thing we have to tackle. That was very insightful. That may be a good query.
Q: So perhaps convey it to the highest degree of the menu if the temperature is under 40?
Lawrence Ziehr: Convey it to the highest degree, you are proper. That is sort of humorous that you just introduced that up as a result of that’s one thing I believe that we’d like: to place it prominently in entrance of shoppers, perhaps as a perform of the state of cost and ambient temperature. These are glorious concepts. And I believe that you just’re considering is in precisely the correct place.
Q: While you’re driving these automobiles within the chilly, what is going on on with the batteries in that chilly climate?
Lawrence Ziehr: I believe that that was one of many highlights that we had been experiencing is that by the chilly automobiles had been experiencing, they had been sustaining nice temperature and in our means to make use of waste power or saved power and people methods had been working, completely no downside. It is not such as you’re driving down the street and also you’re dropping that power. It is saved up and it is truly one thing that we’re capable of faucet into and make use of.
The battery or the [thermal] methods truly are capable of thermally retailer up a big quantity of power that we use for it. We’re speaking kilowatt hours of power that we’re capable of offset electrical power. Driving round, it nonetheless maintains it, it does not dissipate. In a single day you would see it drop by 10 levels or some temperature relying on the configuration. Large batteries can retailer [heat] longer than small batteries, which is sensible.
Q: What was your ambient temperature there?
Lawrence Ziehr: In the course of the day we had been hitting round 10-to-15 levels Fahrenheit with a wind chill of in all probability minus 20. I imply it was windy and we did an interview in that it was chilly.
Q: What was it doing with the HVAC within the automobiles? How laborious a load has that placing on the batteries to maintain you from freezing?
Lawrence Ziehr: That’s one factor that we actually have been making an attempt to grasp is “What’s that load?” and that is an enormous a part of that journey. Power conservation for our system occurs on a regular basis. We’re consistently wanting on the knobs to enhance power optimization. We’re taking a look at methods of offering consolation to the shopper and doing it most effectively and even in these ambient temperatures.
One of many huge components of the journey is definitely understanding how these methods had been working whereas offering consolation. We’re making an attempt to do final power restoration. The system that we’re answerable for, we’re actually making an attempt to optimize the power utilization, and we’re capable of see that driving round. Are we not fogging [the car’s windows]? Are we offering consolation and, and all of these items that we’re making an attempt to stability in opposition to power utilization and defend that thermal power and extra importantly {the electrical} power.
You do not need to get batteries chilly. As a result of then you definately begin dropping usable vary. That means [electrical energy] continues to be there, however you may’t get it out. So that you need to defend that. However the fantastic thing about it’s that you’ve got waste power that is being produced. We now have a sophisticated warmth pump system to go after that, get it, pull it in, offset electrical power, and permit these automobiles to go farther within the chilly. And we’re capable of display that as a result of there’s an important instance of the expertise.
Q: So the warmth pump is not simply used for cabin heating? It is used for battery heating as properly.
Lawrence Ziehr: The thermal system is architected in order that we will defend the battery. The [cabin] warmth pump system can tie into it to drag power from that. However all of the power needs to gather within the battery first, proper so it is sort of a main storage. After which as soon as now we have it there, then we will transfer it out proper again into the battery.
Q: This restoration system works by having cooling jackets on motors and energy electronics after which routing that warmth over to the battery?
Lawrence Ziehr: Yep, simply connecting these thermal methods collectively. However when now we have a related thermal system then we will transfer power freely by the car. Superb.
Q: Out of your journey, what was the takeaway? What did you be taught that you just would possibly change now, now that you just’re again?
Lawrence Ziehr: One of many huge ones proper that conditioning. I believe we have to actually sort of put that entrance and middle within the schooling of that. I believe that is an enormous piece of it. I believe there are some areas of additional optimization we will do. I believe it was affirmation of plenty of stuff that we had carried out already, that contribute to power effectivity.
So actually, we’re making an attempt to grasp the ramifications of some of these things. That means, “Is the view well worth the climb?” If we push this power effectivity too laborious, may we expertise extra fogging? Possibly we should not go that far as a result of that is one thing clients could not agree with or have problem with. You do not need to fog a automobile for those who’re driving down the street. I believe there are issues there that we have discovered that we perceive. So we have established actually good standards there that we will truly roll again and additional enhance optimizations.
Q: How a lot further driving vary do you assume you may attribute to the power restoration system retaining the batteries hotter?
Lawrence Ziehr: On the street, we had been experiencing kilowatts of power offset. And while you’re speaking a 500-mile journey, that provides up fairly considerably. It is tremendous cool as a result of it is like that is actually power that we would want electrically if we did not have this superior warmth pump system. And it’s simple to quantify. And it’s tremendous, tremendous thrilling as a result of we’re speaking to kilowatts of power. That is like your ground [space] heater. Like this electrical ground heater that you’ve got sitting within the nook of a room. It is extra power than that.
Over lengthy journeys, it actually provides up. And, I’ll inform you this, we obtained to the up and we’d not have made that journey if we had been utilizing straight electrical energy. It could not have made it if we did not have the superior warmth pump system. We’d not have made that vacation spot. We’d have needed to cease [to charge], and we would should reschedule the entire deal up north as a result of we would not have made it. So it was actually important for us. It is sort of enjoyable as a result of we will speak about these items on a regular basis, however to really expertise it, it is like, “Yeah, it labored! Glorious.” That’s in all probability why I am sort of jacked up about it simply coming off that journey.
