Recent content by Trancela

Because you were wrong. That was just one of the conjectures. "no brainer"? You brainlessly dismissed that they may stuff fewer cells in a group, thus implying they were using different sized modules.

Charge energy for a cell is greater than discharge energy for the cell. Anywhere from 6% to 10% loss between charge and discharge of a cell. I wonder if the 237 Wh/mi is wall to wheel or battery to wheel? 256 Wh/mi wall to wheel translates to 237 Wh/mi battery storage to wheel.

More speculation: The reason the module can fit up to 25 groups (instead of 24) is that all modules contain 25 groups, but one is a spare, and not in the 96s loop. Assuming there is no way to remove or insert a group of cells, when one cell goes bad, the group is bypassed (or shunted after...

Just as I had speculated -- that the groups (not modules and not the 96s voltage) are smaller on the T3.220. @scaesare So we have 4s24s46p for the T3.310 and 4s24s32p (or 31p) for the T3.220 - probably in a 24s46p module - i.e. 14 vacant cells slots per group. What I don't understand is why...

Note that there are certain overhead elements in a cell. The center folding line which is a dead space at the center of the cell would be the same for an 18650 and a 2170. So this favors the 2170, i.e. more internal volume efficiency. Also there is less steel casing per volume in the 2170...

With pouch cells, it is possible to achieve higher C rates for charge and discharge. I believe this may be due to the superior cooling capacity of pouch cells. The Leaf, Volt, and i3 all use pouch cells. In fact only Tesla and a few odd-lot companies use cylindricals.

How did you arrive at 285 EPA from 72.5 kWh? I doubt that the T3.220 will be a 300 V machine. I am pretty sure they will stick to 400 V, or they will have to change a lot of electronics. Thus if the T3.310 is 8s12s46p, then the T3.220 is 8s12s33p rather than 6s12s46p (which has too much range).

That is pretty plausible. My own estimation based on 51/54 kWh indicated a pack of 3s32s43p, assuming 3 modules, as per Tesla. The 96s is pretty standard. You propose 8 modules for 8s12s46p. As much as I prefer this architecture where modules are low-voltage, I think we should take Tesla...

Yes, if there are 3 modules, then the T3.220 will only have 2 modules. Alternately, it could have 3 modules, but with only 2/3 cells in parallel. I.e. instead of 43P it would be 28P, with 15 of the cells being vacant in the 43P bay. A third possibility is that the 220 has 3 modules but the...

Yes, it is possible that the T3.310 is 3P96S14P. The reason for the 96S is that it both the TS and the Leaf are 96S. It is a good number as it is divisible by 12, and thus lends itself to smaller low-voltage modules in series. Do we really want car mechanics to be dealing with modules that...

Funny. I provide the numbers, and you call it conjecture. You provide no numbers, and you call it the truth.

" Musk said the car is using a smaller number of battery cells (three modules as opposed to the 16 found in the Model S)" from Tesla Model 3: Everything you need to know If true, then I believe the T3.310 architecture is 3M32S43P or possibly 3M96S14P. The latter architecture implies that the...

Problem with the chart that shows price per mile of range is that it is a linear model, while we value range not linearly but logarithmically. The first mile has a lot more value than mile 101. And mile 101 has a lot more value than mile 201. In other words, an EV with range 100 miles is worth a...

Assuming the two battery sizes for the T3 are 51 kWh and 73 kWh (or 54 and 77 after including unused buffers), then the difference of 23 kWh will be made of 96x43x23/77 = 1,233 cells. Also assume that all the electronics and motor are identical - the charger being the exception. Based on the...

I suspect the newer chemistry also increases the C factor above the current 3C, and reduces the internal impedance. Such as is with the 5C Samsung 18650.