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Great idea for batteries

Great idea for batteries

I am in line for the Model 3 and I currently drive a Chevy Spark EV, which has a 19Kw battery and I get about 80 miles a charge. That actually works pretty good for me since I drive under that daily. it seems the larger the battery, the heavier the battery and it takes a whole lot more battery to go fewer miles as the weight piles up. It would be very innovative of Tesla to offer spots for (3) 30Kw batteries per car. Each battery weighs about 450 pounds so you can see how that can add up. By my guess if you had just one 30Kw battery the car would go about 140 miles. (2) 30KW batteries would get you about 215 miles and (3) 30KW batteries about 280 miles. The numbers may be a bit off but the point is the lighter the car the more efficient is runs. Lets say for the most part you only need the (1) 30KW battery. You buy the second one which sits on your garage floor and keeps charged. That one day you want to drive further you push a button in the morning and load up your second battery and YAY you now have a 60Kw battery car. Maybe a couple years go by and you pick up a job that requires a longer drive, go buy that third battery and plug it in. This also allows someone to buy into the car cheaper and buy more battery as they can afford it.

Red Sage ca us | 2016年4月12日

Tesla Motors battery packs already have roughly twice the energy density of anyone else on the market. That ratio will improve further with Model ☰. Whatever amount of energy is within a certain volume of space or given weight in a FOCUS ELECTRIC, SPARK EV, or BOLT EV, the Model S would likely store twice as much. I expect to see about a 40% improvement over that with the technology of Generation III vehicles.

bob | 2016年4月12日

Red Sage, I agree with you 100% on that one. Tesla makes a great battery but it's still a really heavy element to the car, and an expensive one. Another great point on having separate battery packs in the car is if one would fail, the other would still be working. I know it's rare but I have seen a video of a Tesla that had the battery go. Tesla took great care of that customer but the car was out of commission for a couple weeks. if that car had two smaller batteries that customer would not have needed a tow and probably could continue using his car until the new pack arrived and could be installed.

scott | 2016年4月12日

Great idea Bob.

yongliangzhu68 | 2016年4月13日

So how exactly does pushing a button pickup, move around and install a large 450LB object?????

Supraman | 2016年4月13日

I like this idea. However, wouldn't there be implications for suspensions settings and handling characteristics with such a variation in the weight and centre of gravity of the car?

Could some of that be counteracted with air suspension?

dd.micsol | 2016年4月13日

@wj Well I can think of one. Remember the battery swap stations that would change your battery for you?
Perhaps these could be battery upgrade options for purchase instead of swaps. Say you do get a better paying job further away or you plain just want a bigger battery-you drive to one of these locations and swipe your cc and wait 2 min-new upgraded battery pack installed and drive away. Now these stations would be rare but as model 3 comes to light-maybe they could have 2 or 3 in a quadrant that you could drive to on a weekend getaway or something. It's an idea but more tesla cars need to be on the road to make this a viable option.

dsvick | 2016年4月13日

@bob
How much would the "push a button in the morning and load up your second battery" cost to buy and install in your garage? I bet it would probably be less expensive to just buy the second battery outright. Not to mention that anything left on my garage becomes filthy in a matter of days, and I'm sure I'd trip over it on a regular basis too.

yongliangzhu68 | 2016年4月13日

This would require you to dig up your garage floor and build a small room below where you car sits so you could clear the battery pack and install equipment. You would need to install, power and maintain tens of thousands of $ in equipment too. It would also leave a dangerous depression containing industrial equipment that people could fall into.

dsvick | 2016年4月13日

@wj - It would be cheaper to have the new battery stored on the ceiling, and have these big arms come down, grab your car, flip it over, install the new battery, scratch its belly, then put it back down. And, as a bonus, you could wash the roof glass while this was being done.

Hi_Tech | 2016年4月13日

@bob - I like where you are going with this. As you can tell from the other comments, there are challenges to your idea (another one is that the battery pack is used to reinforce the structure of the vehicle, etc.), but at least you are thinking out of the box.

bob | 2016年4月13日

Wow, good concerns. I am thinking this device is either pneumatic like a car jack where you pump it up or it's electric and you position the device under the car and it lifts the battery into place. Or the car can have a device to lift it into place, it would be as simple as getting the spare tire out from under a minivan. it would be similar as the battery swap idea but smaller and you can have it on wheels so you can position it or you can move it out of the way when not in use. Also what about those people who have two Teslas. Maybe most of the time one has one battery and the other has two but when they go on a long trip they put all three in one car.
Interesting notion about the handling of the car. I would think the first one is in the middle, the second would be toward the back since there are people in the front. The weight per pack is about the same as 3 people so it's like being concerned about the handling of the car if you have 3 people in the back seat.

yongliangzhu68 | 2016年4月13日

@ bob: The battery pack is probably around 5" to 7" tall not including the pneumatic jack which would add another 2" for more. How do you get the car up and over this (or it under the car). Next you will need to align within a couple of MM in all directions before you jacked it up. If you can figure out the fist two how do you tighten the bolts to hold pack in place (this is a BIG one that MUST be done to tight tolerances)? This are many other problems that must be addressed also. It is NOT analogous to changing batteries in a flashlight. This is a very complex and heavy duty operation. It looks like even Tesla was not able to make it economical on a large industrial scale and has abandoned the idea.

jordanrichard | 2016年4月13日

Bob, the car's ground clearance is 6 inches, the battery pack is at least that thick. Where is the room to put this lifting device, plus the height of the pack itself?

Battery swapping is not going to happen in anyone's home. Battery swapping stations are also not going to happen apart from the one they already built. The cost to either convert a building or build a whole new one outright is far, far more than the report $400,000 is cost to build an 8 stalls supercharger site. Also, there are essentially no moving parts to a supercharger versus the immense complexity of a battery swap station.

Roamer@AZ USA | 2016年4月13日

Lots of complexity for little gain.

I remember when Tesla dropped the 40 because no one was ordering them.

Ross1 | 2016年4月13日

"not like swapping torch batteries"

Oh, but if it was!

Feed 10,000 18650s down one hole and suck them out another.
Maybe an opportunity for the Dyson EV.

bob | 2016年4月13日

I am a bit of a gearhead so jacking up a car and installing a battery doesn't seem difficult to me. The battery holder can be on a rack with side wheels a bit like a creeper for crawling under a car with. One reason I like this idea is what if your second battery was your powerwall for your home. I can charge that battery at night when cheap or during the day with my solar panels and use my other battery to drive around with. then that one time every couple of months when I take a long weekend trip I jack up my car and install that second battery, or third and off I go. I won't need that battery at home since I am a couple hundred miles away. This is not a daily event but a few times a year. Lithium may end up being a rare commodity so lugging around more than we actually need may in the long run be a problem.
Another reason I am interested in the smaller batteries is I plan on racing the car, not serious racing but once a month have fun racing. The lighter the car the better it goes, turns and stops. As for just driving around town the lighter the car the better it also performs and the less it feels like driving a boat. Glad to open conversation with like minded people

Red Sage ca us | 2016年4月13日

bob: Please stop by the website for Faraway Future. Their Concept Car was a showcase for this type of idea. I'm sure your notion would be accepted more readily in forums dedicated to their endeavors.

Tesla Motors does things another way. They have a uniform size and shape of battery pack enclosure used as a structural member of the vehicle design. That battery pack enclosure includes multiple modules of battery cells. The more modules, the higher the overall capacity.

The interconnection of the array of battery cells within modules, and from one module to the next determines the potential output of the unit as a whole. This works well. No need to change it at this time.

bob | 2016年4月14日

Red, you are an informative person. Tesla, and any large car company, needs to think of one product that everyone wants. Most people don't like modifying or working their car, they just want to get in and go and if we are lucky they at least wash their cars. Thanks for the Faraday link, cool car.

Hi_Tech | 2016年4月14日

Slight deviation from original concept: Considering the Model 3 will have tow hitch option, does anyone think a extra storage tow with extra batteries be something Tesla could provide?

Basically, it'd be like a small storage container, with a battery pack as the "floor" (similar to the cars). Good for extra long distance trips.

I'd think it'd cost quite a bit though... cost of a full battery pack, essentially.

jordanrichard | 2016年4月14日

Physically sure they could, but they won't. Tesla is trying to have EVs be taken serious and accepted by the main stream public. Now, imagine how ridiculous it would look that an EV needs to drag extra batteries with it to get anywhere. Yes, I know it would only be used in certain situations, but that would not be the impression 1 single picture of such a set up, would convey.

Hi_Tech | 2016年4月14日

Agreed.
In fact, I wouldn't really want one anyway. Assuming it'd be too expensive anyways, compared to a simple trailer.

yongliangzhu68 | 2016年4月14日

@HiteshBhatt: That is a more plausible idea. I do see a couple of problems besides costs. Could be a safety or NHSTA issue with 'exposed' high voltage wiring connection. Another big problem would be meeting the criteria of each customer. Some people want an open trailer, some want inclosed, some want short, some want to pull a jet ski. some want......the variations of what meets the individual towing needs are almost endless.

Ross1 | 2016年4月14日

What would be really great is if you could dump in the energy to the car in liquid form, then you only need to put in what you intend to use.
You could have "refilling stations" on street corners.
Then you could directly inject the liquid to the motor/s.
The problem I see is that the motor/s could require thousands of integrated moving parts which to my mind would be impossible, likewise the charging infrastructure, well, it could never happen , could it?
But the technology could last 100 years given government backing and subsidies.
And the noise emission could be rather nice.
Fuel waste emissions: I guess we could get used to it, like the heat from the batteries.
Fire risk? We could get used to it too.

So just imagine, a liquid energy station on every corner, streets full of liquid propelled vehicles, cars, trucks, planes.
Such a great idea, I might share it with Disney studios, or someone doing science fantasies.

Ross1 | 2016年4月14日

That took such a long time to load I thought the spam bunny might have got it.

TeslaTap.com | 2016年4月14日

While I'm not convinced the replacement/changeable battery makes much economic sense, TakeTwo has a surprising solution that can vacuum out low SOC cells and replace them with a new charged set. The whole system is a bit crazy in concept, but actually makes sense and could work. They claim it only takes 3 minutes to suck out the old batteries and replace them with new ones. http://www.tanktwo.com/

It seems far simpler than trying to jack up 400+lb batteries. That said, any replaceable solution is going to add costs over a fixed unchangeable battery pack.

georgehawley.fl.us | 2016年4月14日

Let's resurrect the Model X trailer pack idea for the M≡. Let's say 200 kWh in the trailer plus 50 in the car. Suppose you get 2.5 miles per kWh. (400 wh per mile vs maybe 240 for an unencumbered car). Then you could drive for 500 miles without stopping.

mos6507 | 2016年4月14日

TankTwo is a very cool idea. I'd be worried about physical stress from moving the egg-shaped batteries around (or being crushed from sitting at the bottom of a large silo) as well as how securely seated they'd be once they settle in the tank. You'd also likely have very uneven wearing (or duds) accumulate. But I'd like to see where that idea winds up.

Ross1 | 2016年4月14日

Tesla Tap: I just proposed that back in this thread

bob | 2016年4月18日

There is a guy who does a lot of really cool video's at electricsamba.com where he has converted his VW bus to an EV and in one segment he shows how to make your own trailer battery pack so you can go longer distances. it's a good idea but you also have that look of trailering more batteries. I think what was made clear earlier in the thread is that most people don't want to fiddle with their car this way.

When it comes around to ordering my Model 3 I think I will want high performance and the small battery. Not interested in lugging around several hundred pounds of extra battery for that rare long drive.

NKYTA | 2016年4月19日

TT, how are you going to suck out those batts, and put in new ones and have top of the line cooling and heating?

Isn't this were TM excels? The temp battery management side?

Not arguing, just wondering.

We, of course know where such cells might come from,,.;-)

Supraman | 2016年4月19日

bob - You said "I will want high performance and the small battery".

Unfortunately I think a larger battery is required for the high(est) performance.

dd.micsol | 2016年4月19日

LOL.. disconnect your powerwall and haul it behind you for 1200m of charge. Funny but could be something there-I just wouldn't want to charge it up once it was discharged unless you were staying somewhere for a week with a very high juice socket.

Red Sage ca us | 2016年4月19日

Do not be surprised when the base Model ≡ in RWD has well over 300 HP.

georgehawley.fl.us | 2016年4月19日

@Red: It might be smart to use an existing drive unit to save engineering costs and gain economies of scale. A logical choice would be the drive unit used in the front and rear of all non-performance AWD S and X models. It develops a little less than 300 hp but close.

dd.micsol | 2016年4月19日

I'm getting dual motors and expect about 450hp. No sport or lud. Don't want that much speed surge.

dd.micsol | 2016年4月19日

@george-Elon said the motors will be new and not what you see already. To be lighter, more durable, and more distance. So the tech is to be new. My guess is perhaps just a little smaller and simpler to build to reduce time building them.

Haggy | 2016年4月19日

There's already a thread about this in the Model S forum. It's been discussed in detail and it's not practical for any owner to work with something so heavy, and the battery is part of the structural integrity of the car. The weight has surprisingly less effect than you might think. Somebody calculated that based on the number of cells added to the 85 vs a smaller battery.

Ross1 | 2016年4月19日

The battery packs are organised in packs of seies and parallel.

By altering this config TM could tune for highr guts and shorter duration.
Just a thought.

10 km range @ 2500 amps? 0 to 60 in 2.0

Badbot | 2016年5月8日

Has anyone here actually used a battery swap station? I would like to hear what it was like. do you need to return and have the original put back?

fritter63 | 2016年5月9日

Another idea for making this feasible:

- Car would park on "ramps" in the garage which would be easy to install and give it a couple extra inches of ground clearance. You know those ramps you use to drive your car up on so you can work on it? Just longer versions of those. Relatively easy to install.
- The battery pack would sit in between these.
- The auto pilot on the car could be used to position you very close for alignment. (you would calibrate it once the ramps are installed).
- The battery would be retrieved using (strong!) cables that retract into the chasis with small winches (or a single winch hooked up to four spools.
- Because the cables are flexible, it's easy to just hook them on the battery attachment points, even if not perfectly aligned.
- As the cables are retracted, they pull the battery into alignment where it needs to be. Further alignment is done by 4 conical shaped alignment pins that mate with recesses in the battery pack.

Hi_Tech | 2016年5月9日

@ed - I did not use the battery swap station yet, but believe the concept was that you would do a temporary swap only. Meaning that you'd have to come back to get your original battery pack put back on your car. That said, I'd like to know the reactions/experiences of those that have use it as well. I'm assuming it wasn't as exciting as everything else, considering Tesla has stopped work on that area.

Remnant | 2016年5月9日

One thing that I don't see in these imaginary battery-swap procedures is a provision for reconnecting the coolant circulatory system, which is a must, unless battery cooling becomes solid, such as a Peltier bimetallic system, which would be a mere.plug-in system.

The other issue concerns the fording capabilities of the car. Using your Tesla as a flood rescue pod is not an immodest quest; it only calls for water-proofing the power train and the cabin, and, perhaps, developing a simple propulsion system, just to get out of the trouble (the motor wheel spokes could be used for that purpose, if they changed into mini-paddles, according to their angular position on the circumference of the wheel). This amphibious mode would be just a push-button option, to be appropriately summoned in an emergency.

Naturally, battery modules could be separately replaced if separated to begin with. Hence, I would support the separation of the battery into independently replaceable modules. Such a modular replacement could be supported by certain Tesla engineering advances that would be just modestly innovative, even while satisfying to this replacement requirement.

fritter63 | 2016年5月9日

How does the coolant system get reconnected with the current Tesla battery swap system?

Remnant | 2016年5月9日

@ fritter63 (May 9, 2016)

<< How does the coolant system get reconnected with the current Tesla battery swap system? >>

Tesla has never revealed that, AFAIK.

In the public demonstration it showed, its staff managed the procedure quite fast, but it's reasonable to assume they had a high level of expertise and the tools to support it.

I would not expect the regular Tesla Service Center to perform at that level, but much more slowly and with significant risks, such as damage, loss of coolant, etc. Incidentally, these risks may have caused Tesla to postpone sine-die the broad implementation of battery swapping.

Rocky_H | 2016年5月10日

@fritter63, Quote: "How does the coolant system get reconnected with the current Tesla battery swap system?"

That would probably be part of why it's not fully automated. You have to make an appointment, and they have to have technicians there to run the swap.