R2 / R3 battery pack photos from RJ

[Bullwinkle]

I just hope they charge better and have better controls over the thermals than Tesla has been able to achieve with its 4680. If not and this has more to do with cost savings, I don’t believe it’ll work out well in the long run.

Thermal management does hamper charging speed in the R1

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[RivianRiverRat]

Should we assume this is the large battery pack then? Playing with chatgpt for numbers, I was getting an estimated range of 310-333 depending on the Wh per cell.(111-119Wh). They did say the large battery pack would get over 300 not the standard.

reading thru the purple haze
Based on the patent thread -
How R2 / R3 Scroll Wheels Functions Will Work (From Patent) | Rivian Forum - R1T R1S R2 R3 News, Specs, Models, RIVN Stock -- Rivianforums.com
Range of 314 miles but no idea on battery pack size (my opinion is large pack)

 

[savethemanual]

Yeah, that SOC for the range doesn't make sense though...

 

[kurtlikevonnegut]

I think the potential for a decent m/kWh is there, maybe 3.1-3.3 miles/kWh real world if they can get it around 5k lbs. For a 90 kWh battery if EPA is 3.5 that is 315 range at 100%.

I base my assumption on the Jeep GC Overland I had, it came in at 4,980 pounds with a V6 and I could get 22-24 mpg on freeway trips. Looking at that body style it was more aerodynamic than it looked at .37.

Rivian claims .30 on the R1S so I assume the R2 will be similar.

I think more crucially (for me at least) than the rated range is the fact that a 30% smaller battery pack should charge 10-80 more quickly, especially if they can improve the thermal performance with the new pack.

 

[Dirtman16]

I think more crucially (for me at least) than the rated range is the fact that a 30% smaller battery pack should charge 10-80 more quickly, especially if they can improve the thermal performance with the new pack.

Yeah, they need to be able to get the 10-80 time from 40 minutes down to 25. That would be much more reasonable, and should be doable with a smaller pack and better thermals.

 

[kurtlikevonnegut]

Yeah, they need to be able to get the 10-80 time from 40 minutes down to 25. That would be much more reasonable, and should be doable with a smaller pack and better thermals.

Even without drastically improved thermals, the 10-80 should be quicker in proportion to the difference in battery size. A 35% smaller battery should be able to get that 10-80 charge under 30 minutes.

If they can get it down to 20 minutes reliably on RAN and Tesla I'll be thrilled.

 

[Viking80]

I wonder what the cooling will be like and if they learnt lessons from R1.

The R2 appears to be ribbon cooling on both sides of each 4695 cell. The R1 modules (2170 cell) were bottom plate cooled and shared between a top and bottom set of cells. Either option is acceptable as long as the thermal system is sized right.

Hopefully with the larger cell and ribbon cooling on both sides, Rivian will crank up the power >250kW through 50% SOC for charging.

 

[RivianRiverRat]

Yeah, that SOC for the range doesn't make sense though...

yep - but my best guess is the 314 is TOTAL based on the graph view
upper banner may be stationary and may be able to toggle between the % and miles on the graph and lower banner

 

[Bullwinkle]

The R2 appears to be ribbon cooling on both sides of each 4695 cell. The R1 modules (2170 cell) were bottom plate cooled and shared between a top and bottom set of cells. Either option is acceptable as long as the thermal system is sized right.

Hopefully with the larger cell and ribbon cooling on both sides, Rivian will crank up the power >250kW through 50% SOC for charging.

This is important for easier road trips, but also to get the rock out of Kyle Conner's shoe.

 

[scottf200]

Hopefully it's the standard/smaller pack. You have to assume they aren't going to get Model Y efficiency numbers with the boxy design and you need to account for buffer top and bottom of the battery.

You are right that I forgot to factor in the lower efficiency due to drag.

That is what most thought about with the R1T tho...

 

[scottf200]

If we use the Chinese 4695 cells in post# 4 as an example, each cell puts out 119Wh X 728 cells = 91,392kWh total pack capacity.

One thing a little concerning regarding the Chinese 4695 cells...

That is quite small for battery life and does make me hesitate when commuting for me will be 90 miles a day to work and I had planned to keep the car for a good 8+ years. I only have one car so it will be my only transportation.

2,000 cycles x 300 miles = 600,000 miles. Unless you have a seriously long commute you will be fine for 8 years. (A cycle is 1 complete charge and discharge. A 50% - 80% charge / discharge = 30% of a cycle).

So 1200 cycles fast charged and 2000 “normal” charged. I think I say the range was quoted as 300 miles? There is going to be a top and bottom buffer as well so driving the full range will be close to but not an actual full cycle, but lets ignore that.

So normal cycles gets you 600,000 miles, with a 90 mile commute (round trip?) you get 6,666 trips, 5 days a week 52 weeks a year gets you 25.6 years. A lot longer then most people keep a car.

If you exclusively fast charge it it is 360,000 miles. A mere 4000 trips. Or 15.38 years. Longer then most people keep a car, but not as long as a car tends to stay on the road.

Cycling example perspective as people often read those cycles as 'daily charges' vs whole 0% to 100% cycles.
>>>>>>>>>>>>>>>>>>>>>>>>

From the following article on batteries "similar" to what Tesla is using.​

​

Divide those number of cycles by 365 or 300 or whatever number of days per year you want. Pretty long.​

​

"500 cycles? But that’s (relatively) low! Yes. But what is not shown on the spec sheet is that when you partially charge and discharge, degradation of the battery capacity is reduced. Thus, you can do over​

40 000 charge/discharge cycles when going from 30% to 70% only. Or over
35 000 charge/discharge cycles from 20% to 80%;
28 000 cycles from 10% to 90%;
15 000 cycles from 8% to 92%,
07 500 cylces from 6% to 94%, and the capacity reduction goes faster and faster, finally reaching
00 500 cycles when recharging from 0% to 100%."

http://blog.evandmore.com/lets-talk-about-the-panasonic-ncr18650b/​

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[jfrieden]

If we use the Chinese 4695 cells in post# 4 as an example, each cell puts out 119Wh X 728 cells = 91,392kWh total pack capacity.

One thing a little concerning regarding the Chinese 4695 cells...

According to ChatGPT, LG's batteries tend to be more dense, have more cycles than most EVE Energy batteries. Would increase the pack size about ~10%, and maybe an additional 20 - 25% on cycle charges.

 

[captainjp]

According to ChatGPT, LG's batteries tend to be more dense, have more cycles than most EVE Energy batteries. Would increase the pack size about ~10%, and maybe an additional 20 - 25% on cycle charges.

Good point. Also, I’m sure Rivian has thought of this and isn’t working backwards like some imply

 

[Viking80]

According to ChatGPT, LG's batteries tend to be more dense, have more cycles than most EVE Energy batteries. Would increase the pack size about ~10%, and maybe an additional 20 - 25% on cycle charges.

Don’t believe everything AI gives you.

 

[NY_Rob]

^ exactly, and given the fact that the Chinese usually always "slightly exaggerate" cell output, they may indeed put out less than 119wH per cell. With that in mind, even if LG's cells do put put more energy than state of the art Chinese cells, you're not getting 10% (which would equate to an extra 12wH/cell) out of the LG cells.

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