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Would a P60D have even faster 0-60 times with a lighter battery?

Would a P60D have even faster 0-60 times with a lighter battery?

Does the 60 have a lighter battery than the 85? If so, it makes me wonder if an easy "mod" that could be done is to swap an 85 battery for a 60 battery, thus drop 150-200lbs and have a sub-3.0 launch?

Or is it more likely that the 60 battery would not have enough juice to power a "P" model with dual motors?

carlk | 2 February 2015

S60 is slower than S85. That should give you an indication.

Red Sage ca us | 2 February 2015

It's mostly about the inverter(s) used.

Anthony J. Parisio | 3 February 2015

Some have mentioned they did not reach 60 in 3.2 seconds unless battery was fully charged. I think range is the main reason for lager battery. The speed is a fortunate side effect.

georgehawley.fl.us | 3 February 2015

The 60 has about 2000 fewer batteries in it than the 85 (about 200 pounds worth) but I think they are wired to produce the same total voltage of about 350 volts. If this supposition is correct, the 60 kwh battery pack is limited to about 70% as much peak current which limits the acceleration potential. The weight savings is only a 4.5% reduction in rolling friction.

I'm wondering how fast the car would be if it were made entirely out of batteries connected to an appropriately modified drive train to handle the current. The torque would probably destroy the gears.;=]]

georgehawley.fl.us | 3 February 2015

Alternatively, take out 7103 of the 7104 18650 cells and step on the the accelerator pedal.

Earl and Nagin ... | 3 February 2015

@OP,
My understanding is that the batteries for the 60 and 85 kWh weigh the same. This was necessary for the same safety testing to apply to both.
They could probably reduce the weight of the 60 and spend another few $100M on testing again but it still isn't clear to me whether the reduced power from having fewer batteries would overcome the reduced vehicle mass for acceleration performance.
@Anthony J. Paraiso,
The battery size was to get to 100,000 miles of life on the pack of cheap 18650 cells and still have ~80% capacity left. The range, acceleration, and charging speed were fortunate side affects that Tesla capitalized on to be able to start a company that could compete with 100 year old entrenched competitors.

DTsea | 3 February 2015

No, the 60 is lighter than the 85. Thats part of why it gets a little better mpge

EVBeast | 3 February 2015

So if I took my P85D and did a battery swap with someone with a S60, we could do a test!

Rocky_H | 3 February 2015

I thought the 85kwh battery pack uses 400V, while the 60kwh uses 350V. Is that right? This shows in the Superchargers. Bjorn Nyland has this time-lapse of Supercharging a 60 versus an 85. The 60kwh car seems to always be getting about 335V from the Supercharger. The 85kwh car is getting about 370V. (Possibly the supply at that location couldn't push more than 370V?) They were both done at the same Supercharger location and same firmware versions in the cars.

https://www.youtube.com/watch?v=S00RG6uqpPo

AmpedRealtor | 3 February 2015

You can't draw the needed current from a 60 kWh battery. It's not about weight.

Bikezion | 3 February 2015

Yes
No
Yes

Of course a lighter battery would be quicker, assuming it could deliver the same power. (At a reduced range).
Power = Volt x amp Hour x C rating, or more simply volts x amps.
The 85kWh will put out more power then the 60kWh.

Bighorn | 3 February 2015

Rocky
You're right--the voltages are different--part of the reason they don't supercharge at the same peak rate.

georgehawley.fl.us | 3 February 2015

I've never seen a description of the 60 kWh battery pack. I was guessing.
The 85 kWh pack has 16 modules, each with 6 groups of 74 18650 cells in parallel. The 6 groups are connected to each other in series. The result is that the nominal voltage put out by the pack is 16 times 6 times the nominal voltage of a single 18650 cell. 16 times 6 times 3.6 = 345.6 volts. Panasonic spec. for charging such a cell is 4.2 volts per cell. Ideally, then the 85 kWh pack needs in excess of 345.6 volts in order to charge. 16 times 6 times 4.2 is 403.2 volts. ( Max. Supercharger voltage is 400 volts in the US, I believe.) 377 volts will suffice but might be a little slower.

Bjørn's video shows the 60 kWh pack charging at about 335 volts. This suggests that the 60 kwh has 16 modules with 5 parallel groups each. 16 time 5 times 4.2 is 336 volts needed for charging. If this combination is correct, the 60 kWh pack must have about 5000 cells in it. That's about 312 cells per module instead of 444 as in the 85 kWh pack. With 5 groups this would equate to about 312/5= about 62 cells per group instead of 74 as in the 85 kwh pack. Therefore, the 60 kWh pack, if this analysis is right, is only capable of deliver 62/74 = 84 % as much current as the 85 kWh pack at 80/96 = 83% of the voltage as the 85 kWh pack. .84 times .83 = 70% as much power. Hence, less potential acceleration for a car that would be only 4% or so lighter.

georgehawley.fl.us | 3 February 2015

DeliverING that is.