-
Want to remove ads? Register an account and login to see fewer ads, and become a Supporting Member to remove almost all ads.
75 and 75D variants increased performance from July 1st - software and hardware improvements?
- Thread starter Bluejuice
- Start date
I don't think we're saying anything different. My hunch is they'll end with 8, 12 and 16 module packs, the 8 module being the entry 3, the lower voltage accounting for the lower performance.
On 60(software limited 75) the sticker was 75 kWh 350VDC.
I would not worry about not having DU00 or any other code in your spec too much, all current D models are able to get sub 5s 0-60 with the simple firmware update. Eventually, Tesla will provide the option for the upgrade or people find a way to do it themselves.
The voltage comes from the number of modules used. Each module is 25V and they are wired in series. 16X modules gives you 400V and 14X modules gives you 350V. The 100 KWh pack has the same number of modules as the old 90 and 85 KWH packs, but it has more cells per module which results in a higher energy storage (more AH storage total).
If they use the same modules as the 100 KWH pack, which I am sure they are going to start doing soon if not already done for the 75 update (this saves on production costs), the total cell count using 14X of the 100 KWH pack modules gives you just slightly more cells than were used in the 16X modules of the 90 KWH pack. This results in a pack with 350V, but 89 KWH of energy storage.
The difference in voltage will make supercharging slower, but will allow performance equal to the old 90 because the DC is run through an inverter and converted to AC before going to the motors. If the inverter is made correctly, the DC input voltage doesn't really matter that much.
If they are trying to hide an upgrade like they did when going from 70 KWh to 75 KWh, the battery sticker probably still says 75.
Using 12 modules will result in a pack that's only 300 VDC and will supercharge at 75% the rate of the 100 pack.
From the pictures of the layout of the 3 from the reveal, it looks like the geometry of the 3's modules is different and they use a different battery cell. Due to the different shape of the space, I doubt Model 3 and Model S/X will ever share the same module. Tesla could easily make the modules for the 3 50V each and 8 of them would result in a 400 VDC pack.
Performance largely comes from the power in, which is determined by the number of cells, the capacity of each cell, and the chemistry. The 85->90 was achieved through chemistry changes which improved the capacity of the cell. The 2170 format has more capacity per cell over the 18650 format for the same chemistry.
From wk057's analysis, it looks like the 100 KWh pack has cells with a slightly tweaked chemistry, though these cells might be in the later 90 packs too. Around the time of the refresh the 90 went from 280 to 294 miles range. They may have quietly introduced the new chemistry then.
But the increase in capacity for the 100 KWh packs has much more to do with using more cells. The 100 KWh rating was changed a little too, but the 90->100 probably didn't get much acceleration boost because the car was already limited by other factors, probably the size of the motors.
So are you saying that the first 75KWh batteries going in badged 70s had 70KWh printed on the batteries? So that is why the current crop of 75KWh batteries could really be software limited 89KWh? Or are you saying that the stickers always show the maximum physical capacity regardless of the firmware limitation? So that the current 75KWh batteries are proof that the battery change on which you speculate hasn't happened yet?
Isn't a secret battery upgrade pretty easily exposed by looking at the charge over time supercharging curve? If you take a 100D and a 75D from the same production era when both are at X distance remaining and a half hour supercharging later they both have the same higher distance available then the 75 is a rebadged 100. If on the other hand the 75 has less distance available then the batteries are physically different, since the charging rate slows as the battery reaches physical (rather than unlocked) battery size?
Also, couldn't we just weigh the two similar cars with different battery sizes since there is 86 pound difference between two modules and zero pound difference between a software limited version and its full capacity twin?
I never saw anything on what the battery labels said on the first 75 packs that were really software limited to 70. I assume they had a label saying they were 70 so as to not give away the secret prematurely.
I never saw anyone with a software limited 60 post a picture of their pack label, so I'm not sure what it said.
A small pack based on the 100 KWh battery modules would supercharge slower than a 100 KWh pack because it's only 350V instead of 400V. The supercharger needs to step down the voltage to the pack's voltage which lowers the power transfer rate.
However if the current 75 pack was software limited, the last bit charging to 100% would go faster than with an older 75 pack. It's charging curve to 100% would be similar to the software limited 60 pack. I haven't seen anything where anyone has tested the latest 75s though.
I don't know what the weight of the new 100 KWh pack modules is, I know it's a little more than the old 75/90 pack modules because they crammed more cells in per module. 14 modules of the 100 KWh pack would have 7224 cells, a little more than the old 90. The cooling system on the new modules is a little different than the old pack, so the weight wouldn't be exactly the same and there does appear to be some changes to the motors and inverters (as advertised by Tesla), but if the new 75 was a software limited 89, it would weigh closer to an old 90D than an old 75D.
But if anybody has done that, I haven't seen anything and I read the forum pretty regularly.
Currently there are very few of the new 75s out there, and there aren't all that many people who can do these tests. A scale that can accurately weigh a car down to the difference in weight between a 90 and a 75 exist, but to do it right you should weigh the two cars on the same scale back to back. And make sure there isn't anything extra in either car that can throw off the weight.
The supercharging test to be done right should use some data logging software that only a few Tesla owners are geeky enough to have installed. I'm aware of it, and I've thought about installing it, but I haven't done it and I'm probably on the geekier end of the spectrum around here.
No, the BT codes are kind of all over the map. The original 85 KWH battery was BT85, there was also a BT70, PBT85 was the original performance car battery. My car had the code BTX4 and the description says it was an 85 KWh battery up-gradable to 90, though the upgrade option had been dropped by the time I bought my car and it only came as a 90. I think the original 75 KWH battery was BTX5, though I don't have that in my list of codes.
I would assume there has been a BTX6 and BTX7. One is probably the P100D battery with the fancy fuse and the other is the standard 100D battery with the normal fuse. BTX8 could very well be the new battery with the 100 KWH module. It's a good data point, though not conclusive. When you get your car, please take a picture of the label inside the right front wheel well and post it here. I'm sure a lot of us would like to see any differences from the old 75 battery label.
Would be really interesting to see a similar picture from a 75/75D with the enhanced performance (produced after the19th of June 2017?).
Where can you find this sticker. My Tesla was entered producing on the last week of June.
kev1n
Active Member
I checked my model S's sticker (Build date last week of June), and it had the same exact sticker asside from the serial number...
Similar threads
