Bigger Battery Pack

*Edit: After reading all of this it seems this is a pointless post but I'd like to see other people's input on this or maybe start a discussion on it*

I am trying to figure out the major restrictions we have on a larger battery pack.
First off I need to say my knowledge on this subject is very limited so you'll have to excuse some of my "DUH" comments.

I wanted to compare the Rav 4 wheel base/track vs the Tesla Model S wheel base/track in order to find the available space for the battery.
I know this won't be a perfect method to find the available space since the tires sizes are difference and I'm sure vertical clearances are not the same but I'm just doing ballpark guesses.
The Rav 4 is 61.4" X 104.7"
The Tesla Model S is 65.4" x 116.5" (using the smaller of the two Track sizes)
Using basic math, that is a difference of 1,190.52 in2, or you can say the Rav 4 has 84% the space for a battery than the Tesla.
How is then that they have more than twice the kWh than us? (85kWh vs. our 41.8kWh)
Well so far I have only talked about length x width. Maybe the Tesla's battery is thicker than ours... but surely not that much thicker to the point of allowing for that much larger a battery.
Maybe Tesla is able to utilize more of the space than us since they built their car from the ground up. They probably designed the car with the space reservation of the battery, whereas Toyota/Tesla had to "fit" the battery around most of the existing components of the Rav 4.
Looking at the two pictures below, this seems to be the case.

So, going forward how would we get a larger battery pack into our Rav 4 EV? I guess without re-routing and changing major components, the easiest way to do this is to have a "thicker" battery which would cut into our ground clearance. Of course this is much easier said than done since we would need someone to design the battery from scratch. Let's face it, that's not going to happen.

In the end, it looks like the answer is, we won't be getting an option of a larger battery pack anytime soon (or probably ever).
It's a shame, it seems if the Rav4 was built from the ground up around the battery size, we could probably get closer to 70 kWh (or more!). Of course that means the Rav 4 EV would've been a 100k + car

The one-off form factor will largely prevent someone building an aftermarket replacement for such a low-volume car. Don't expect Toyota to lift a finger.

I do believe there will develop a market of refurbished battery packs that take a core and replace the batteries. You would provide your core and get the replacement. I think the rebuilder could put higher density batteries in the rebuilt battery. You might get 60KWh maybe with something like this when it comes time to replace the battery in 10 years.

Yes, the 2,600 units figure is why I said "let's face it, that's not going to happen" which is, again, really unfortunate.
If this was an on-going production vehicle there could be many opportunities.

Speaking of replacing the battery, is the ONLY reason to replace the battery because of the decreased ability of the battery to hold it's charge? If in 10 years my battery can only hold 60% of it's original charge, and I am OK with that, is there any other reason to replace it?

Khoa said:

If in 10 years my battery can only hold 60% of it's original charge, and I am OK with that, is there any other reason to replace it?

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Some cells could fail and fall outside the operating window and the BMS would throw an error, probably leading to a "Check EV System" message.

That "could" happen from day one, so I don't think that would necessarily prevent further use of the battery pack. It probably would throw a diagnostic "code" of some sort, but should not otherwise prevent continued use of the car.

Dsinned said:

That "could" happen from day one, so I don't think that would necessarily prevent further use of the battery pack. It probably would throw a diagnostic "code" of some sort, but should not otherwise prevent continued use of the car.

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Clearly it can because it already has. At least a couple people have had their whole pack replaced already under warranty. After the cars start to go out of warranty somebody is going to have to figure out how to service the pack at the module or cell level. Nobody is going to want to pay Toyota or Tesla for a whole pack when part of it fails out of warranty, even with a substantial core value.

I suspect that the systems in the car will prevent it from coming READY if it detects a significant problem in the traction battery pack. Whether it should or not is another story.

In response to the OP, the more interesting comparison between the RAV4EV and the Model S is the plan view AREA of the pack itself, not the track & wheelbase or overall dimensions of the car. Also, the Model S has a big bump in the front of the pack which I've heard contains more cells too.

2600 CARB conversions VS a ground-up designed EV, end of story. No chance of feasible upgrades, replacements, etc. Lease a RAV and turn it in for another option in three years. It's a great stop-gap EV for the money but holding out for more than that is like ordering a Myers Motors EV and waiting for delivery to come. One could also wait for the Gen 2 Aptera. Once the charge timer is fixed we can discuss pack augmentation.

miimura said:

In response to the OP, the more interesting comparison between the RAV4EV and the Model S is the plan view AREA of the pack itself, not the track & wheelbase or overall dimensions of the car. Also, the Model S has a big bump in the front of the pack which I've heard contains more cells too.

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I agree, the optimal dimensions to have would be the area of the battery pack... but I can't seem to find that anywhere. I guess I could stroll into the nearest Tesla store with a measuring tape if they're busy enough they probably wouldn't even notice me measuring the battery.

I still think the track/wheelbase size is an interesting comparison to make because it shows us that if the Rav 4 was a ground-up design, it could theoretically have almost the same sized battery as the Model S

And yes 4EVEREV, I agree it's obviously a case of new design vs. reworked design. It's a shame too since the Rav 4 EV is actually a pretty good car (despite all the issues others are having).
3 years from now, I'm still not convinced I'll let this car go. I'm not as up to date with the EV world as some of you; I haven't heard of any other EV SUVs except the Model X which I can't afford. Please someone chime in if there is another SUeV on the horizon. True there will be Plug-on Hybrid SUVs but I'm almost certain it won't be as fun a drive as the Rav 4.
I disagree on the charge timer first then pack augmentation comment. The charge timer is a basic issue that really really really should have been fixed by now. However with that said, the two "enhancements" are on two different playing fields. One is a small software issue that Toyota doesn't care to/is too lazy to fix. The other involves the battery pack which is almost purely Tesla. It doesn't make sense right now for Tesla to offer anything; but in the future when our batteries at 60-70% capacity of what they used to be, they could offer us battery packs greater than 41.8 kWh. They already have all of the engineering data, it's just a question of is it worth it for them to rework the engineering for our batteries for 2600 units, (without knowing how many of those 2600 would actually buy a better Tesla battery).

Quick Edit: Forgot to mention that I was thinking the other day about whether or not Tesla could've made this a better car but didn't want it to compete with the Model X. Maybe they could've added a CHAdeMO port or a larger battery pack. Or maybe the time constraint was just too sporty and they did what they could. 2 years to retrofit a car from ICE to fully electric is just plain crazy.

In 5 - 10 years, perhaps sooner, I suspect that costs of batteries as well as capacity improvements will yield batteries with costs in the $250/KWHr range at moderate volumes that a "hacker could buy to re-firb RAV4s. If they were able to repurpose the old batter for grid storage there would be reasonable valuation for the core. I think be might be able to get upwards of 60KWHr in a RAV4 EV pack by then for an out the door cost of about $15 - 18K installed, given the value of the core and some margin. Imagine getting stretch miles of ~200 mile ranges! Or 150 miles at normal speeds.
Why would this be a good deal? There is no other limber, low cost EV out there nor will there be. The Tesla SUV is HUGE and expensive. I live in the mountains. Those pretty Tesla wheels would be out of round after a week.
Where will this come from? My guess is a combo of Tony Williams and Electric Motorwerks

Khoa said:

... Quick Edit: Forgot to mention that I was thinking the other day about whether or not Tesla could've made this a better car but didn't want it to compete with the Model X. Maybe they could've added a CHAdeMO port or a larger battery pack. Or maybe the time constraint was just too sporty and they did what they could. 2 years to retrofit a car from ICE to fully electric is just plain crazy.

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It's actually hard to see anything they could have improved, outside of DC charging, to improve the RAV4EV given the constraints and Toyota's lack of enthusiasm for the car...which is likely why it doesn't have DC charging. The bigger surprise is that they gave us as much car as they did. It would have been cheaper to make a shorter range vehicle that just barely met CARB guidelines.

davewill said:

Khoa said:

... Quick Edit: Forgot to mention that I was thinking the other day about whether or not Tesla could've made this a better car but didn't want it to compete with the Model X. Maybe they could've added a CHAdeMO port or a larger battery pack. Or maybe the time constraint was just too sporty and they did what they could. 2 years to retrofit a car from ICE to fully electric is just plain crazy.

Click to expand...

It's actually hard to see anything they could have improved, outside of DC charging, to improve the RAV4EV given the constraints and Toyota's lack of enthusiasm for the car...which is likely why it doesn't have DC charging. The bigger surprise is that they gave us as much car as they did. It would have been cheaper to make a shorter range vehicle that just barely met CARB guidelines.

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Yes, I agree. Making the car "too capable" was a big mistake.

The original prototype had two 18kWh packs from the Daimler Smart ED with 2600mah cells from the Roadster. 36kWh total should have been plenty to get the CARB-ZEV "100 mile" range credits, just like it does for the Mercedes B-Class ED.

But, for some reason, Toyota opted for a much bigger pack to arrive at 113 miles EPA range (they could have simply eliminated 80% charging to get that number). I think I know who made this call, and I suspect that the reasoning was "market leader" with a market leader $51,000 price.

Plus, they would have had competition with the Tesla Model S-40 for $57,000.

I really think that they thought these cars would all be gobbled up very quickly, with people paying a premium. Toyota didn't even include any of the $7500 tax credit in leases until July 2013, 9 months after release.