Why doesn't Tesla sell an option that fills the "frunk" with a battery for more range

[scottm]

The 85KWH battery weighs 1200 pounds not 700. Whether the batter is "full" or not has no change -- Electrons don't weigh much.

tesla battery weight - Google Search

Yes they do weigh something. Heard the estimated weight of the information flowing on the Internet today is about 62 grams.

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..Besides, I don't want my frunk taken up by anything else. I'd have to get rid of the propane heater in there that I pipe into my car in winter.

 

[Aljohn]

@scott.... a propane heater.. It must be really cold in the winter in your part of Canada (hey). Get rid of that. I will hear the explosion all the way down here in Atlanta.

 

[Navyguy]

Yes they do weigh something. Heard the estimated weight of the information flowing on the Internet today is about 62 grams.

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..Besides, I don't want my frunk taken up by anything else. I'd have to get rid of the propane heater in there that I pipe into my car in winter.

62 grams per electron? dude WOW. where in heck you get that figure

The textbook values are: proton: 1.672621777 ×10−27 kg neutron: 1.674927351 ×10−27 kg electron: 9.10938291 ×10−31 kg (more than 1000 times lighter than a proton!)


An electron actually weighs about 0.00054amu. This is so much less than the mass of a proton or a neutron that the mass of the electrons is ignored in determining the mass of an atom.


That means if they ingore it on an atomic scale you can DEF ignore it on a macro scale lol

 

[Larry Chanin]

The current weight of the full battery is only about 700lbs.

Do you have a source for that information?

For an 85 kWh battery pack the cells alone weigh about 770 pounds. You have to add the battery casing, thermal protection, coolant, electronics, etc. to obtain the pack weight. I have seen unofficial estimates for the battery pack in the range of 1200 to 1600 pounds.

Here's one unofficial source that quotes a weight of 1323 pounds. Why Tesla Rules: Huge Battery With Small Cells

The battery of Model S Performance weighs 1,323 poiunds.

Larry

 

[ithaclies]

I just thought of this today - yes the extra cargo capacity is great, but why not an option of an extra supplemental battery pack either in the frunk or that uses up some of the trunk space in the rear? Is there an engineering reason I haven't thought of or would nobody buy it?

I couldn't agree more. The model S is supposed to be able to haul 5 adults and two kids. The average adult male in america weighs around 195 lbs and a kid weighs around 50 lbs, so the car should be able to handle an increased load of around 900-1100 lbs. My Prius V has a similar capacity. The weight distribution with a driver is almost 50/50 as is, so the more logical idea would be two small battery pack expansion slots (25kwh each), one in the frunk, and one in the back under the cargo floor. I get what the rest of the guys are saying on here about cost and such, but weight arguments are total bunk. I drive over 2000 miles a week hauling over 500 lbs at times in my Prius V and it never seems to effect the car in any crazy measure. Slightly less efficiency, slower accelerations, longer stopping distances at high speeds as you'd expect under full load, but in NO WAY to the extent that it hurts the car's abilities enough to matter. I drove to Penn State from Cincinnati with around 875 lbs in the car (myself included in that figure) and my mpg dipped by a whopping 2 mpg. So seriously, it's not a weight issue. At the very least, there should be battery expansion packs available. Or maybe, expansion bays where you can open it up like the back of a child's toy or a boombox radio and just add 18650 batteries when you need more range. You could jump on ebay (or buy them directly from Tesla , and get extra range out of your car one vape mod battery at a time if you so choose. Sooner or later it's going to be a hack someone does to EVs. Tesla should get ahead of that curve and make it happen. Guys who drive over the max range of the current Tesla models like me are holding back from buying one directly because of the range issue. If I got a delivery to make 400 miles away, and have to stop for an hour or more to charge, that's an hour that's costing me money. I'm not saying put more batteries in every car, just make the battery expandable for the individual owners.

 

[scottm]

Could you imagine an EV world whereby a battery module pack had a standardized form factor, and every car had a number of bays ready to slot these batteries in... for extra range, less range, or for swaps at filling stations along the way.... Really burly guys would hoist 300lb packs into cars all day long, or a robot arm would, more likely.

 

[artsci]

I just thought of this today - yes the extra cargo capacity is great, but why not an option of an extra supplemental battery pack either in the frunk or that uses up some of the trunk space in the rear? Is there an engineering reason I haven't thought of or would nobody buy it?

Is range a problem for you? With the supercharger network, not for me. Of course it could always be better but the trade-offs make no sense. I've not a had a single instance in nearly four years of ownership when I was in serious danger of running out of juice, and that includes a coast to coast drive two years ago. There are other major problems that Tesla needs to make a priority, namely parts and the speed of service, and range is not one of them.

 

[berkeley_ecar]

How about SAFETY. Just as I'm happy not having to worry about having a huge engine thrust in my face in an accident, I'm not eager to have a battery pack play the same role. Let's leave the front as a crumple zone and added storage area.

 

[ithaclies]

Actually, with solid state batteries, there wouldn't be a need for high-speed swapping stations because the batteries will charge insanely fast. We're around 5-10 years before they will be viable in cars, but the time it would take to build such a battery swapping infrastructure would be a waste because it would be obsolete by the time it became accessible to everyone. That's another reason I shared my idea earlier. It's current technology, it's logical, and it's more economical for the manufacturer. 100 mile range EVs with expandable battery bays that cost as much as an economy car. Do this and gasoline cars will decline real quick, battery manufacturers & resellers will be making ridiculous profits, and people don't have to base their car buying decisions on range.

 

[ithaclies]

How about SAFETY. Just as I'm happy not having to worry about having a huge engine thrust in my face in an accident, I'm not eager to have a battery pack play the same role. Let's leave the front as a crumple zone and added storage area.

A 25kwh pack wouldn't take up that much space, even so it wouldn't be that hard to design a more spread out pack that keeps the crumple zone from being negated, and the frunk is already designed to handle the weight. With all the safety features of the model S, worrying about front end collisions the way you do makes everyone else driving with ICE engines seem like blindfolded daredevils.

 

[MSDadMich]

How about SAFETY. Just as I'm happy not having to worry about having a huge engine thrust in my face in an accident, I'm not eager to have a battery pack play the same role. Let's leave the front as a crumple zone and added storage area.

Agree with above.. safety implications could not be understated more here... that 5 star frontal rating would be toast with a crumple zone similar to ICE vehilces... front battery would act very similar to a gasoline engine in this area. Also, with safety in mind again, keep in mind that the current battery packs are bullet-proof! Those batteries are encased in a very stiff, very durable metal container under the car for safety and cooling/heating when needed. Besides, with the best charging network in the world by far... do you really need a larger battery at the expense of safety? Wait for new bat tech to come out instead.

 

[ithaclies]

I've not a had a single instance in nearly four years of ownership when I was in serious danger of running out of juice, and that includes a coast to coast drive two years ago.

That's all well and good when you have the free time to kill during charges. A lot of people are on a constant state of movement from sun up to sun down, and stopping every 250+ miles to recharge is a lot of downtime that costs you hours of productivity.

How about SAFETY. Just as I'm happy not having to worry about having a huge engine thrust in my face in an accident, I'm not eager to have a battery pack play the same role. Let's leave the front as a crumple zone and added storage area.

Agree with above.. safety implications could not be understated more here... that 5 star frontal rating would be toast with a crumple zone similar to ICE vehilces... front battery would act very similar to a gasoline engine in this area. Also, with safety in mind again, keep in mind that the current battery packs are bullet-proof! Those batteries are encased in a very stiff, very durable metal container under the car for safety and cooling/heating when needed. Besides, with the best charging network in the world by far... do you really need a larger battery at the expense of safety? Wait for new bat tech to come out instead.

I'm not talking about retrofitting old ones with a pack someone slapped togeather and sold on Ebay, and just letting it bang around in the frunk while driving. I'm talking about future models having a similarly safe encasement designed into the frunk that is accessable for adding batteries. Yes, in that case I would most definitely want one there. Also, why the fear that you would be in such an accident in the first place is lost on me. Hasn't this car been one of the most least crashed vehicles on the road since 2012?

 

[pinball_player]

The problem in my mind is say you add 20 more miles of range. Then there will be those who need 30 extra miles so that 20 miles is useless. So then you add 50 miles, but someone will need 75 extra miles.

It is a never ending issue.

Just stop and use SuperChargers.

 

[artsci]

That's all well and good when you have the free time to kill during charges. A lot of people are on a constant state of movement from sun up to sun down, and stopping every 250+ miles to recharge is a lot of downtime that costs you hours of productivity.

Maybe some people need to get a life

 

[Quick2Judge]

So my tought was put a new battery connector up there. If you run out of juice tow brings an extra battery with about 50 miles that you drop in the frunk and pay $75/day to rent the pack instead of paying for the tow.

Not sure how many people run out of juice... If it works really be a viable market.

 

[ithaclies]

Maybe some people need to get a life

Nah, they'll get a Prius Prime which has double the range of any Tesla, and costs around 5k less that the Model 3. Time is money, if your vehicle wastes mine, you wont get my dollar.

 

[ithaclies]

The problem in my mind is say you add 20 more miles of range. Then there will be those who need 30 extra miles so that 20 miles is useless. So then you add 50 miles, but someone will need 75 extra miles.

It is a never ending issue.

Just stop and use SuperChargers.

Hence why I said, newer EVs batteries should have expandable power aftermarket. Make the car good, but let the consumer choose how much range it has after purchase.

 

[Miss Winslow]

I know this convo went out a couple years ago, but given the progress in battery density I’m curious what everyone thinks about at least some type of supplemental energy storage to combat range anxiety.

Just wanting to get some honest feedback. Lets say you could purchase a thoroughly tested 15kwh battery pack that would sit either in the trunk, or the frunk, be connected to the native charge supply and be remove-able for emergency situations. Lets say perhaps this pack added less than 100lbs weight to the vehicle and cost around $3000.

Who believes there would be a market for something of the sort?

 

[Uncle Paul]

Right now, there is almost Zero market for this type of additional battery pack. The cost and complexity will stop most people and the engineering necessary to get cleared for the degration of ride, handling, cooling, computer adaptation, crash protection etc will all conspire to make it less appealing.

Many want to go cheap and just get a minimal battery + the ability to add additional capacity for the fringe areas where they will need the range. Not currently feasable.

Same thing with people wanting to get an inexpensive main vehicle, and have the ability to pull along a second battery in a trailer. Again few would actually purchase due to costs and issues.

 

[Galinette]

The car would catch fire at every frontal collision.