That Tesla Data: What It Says and What It Doesn’t

Re:That Tesla Data: What It Says and What It Doesn’t by jacquesm on Thursday February 14, 2013 @07:09PM (#5223548)

Sure it is. But that will only work when you warm up the pack, not when you warm up the car. The draining of energy will also warm up the pack (it should, to some extent because the pack will have an internal resistance which the current passes through, which will turn into heat) but this is still much less efficient than using that energy to propel the car forward.

The band where draining at a lower rate would warm up the battery to the point where the aggregate power taken from the pack would be higher if you drained it at a lower rate for a 1/2 hour and then at a higher rate is a very thin one if it exists at all.

The good news is that that is a thing that could easily be proven or disproven with a bunch of LiPo batteries, a freezer and a bunch of resistors.

I'd be quite surprised if the Ri of the batteries was low enough to allow sufficient current to flow, yet high enough to heat up to have this effect.

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Re:That Tesla Data: What It Says and What It Doesn’t by danielweber on Thursday February 14, 2013 @07:15PM (#5223577)

A car in motion uses ten times the power of a house. The engineers apparently wanted him to slowly pull power from the battery, which would be consistent with "sitting in the car with the heat on low."

If it turns out Tesla denies telling him how he can condition the battery, that would be significant.

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Re:That Tesla Data: What It Says and What It Doesn’t by TillE on Thursday February 14, 2013 @07:20PM (#5223605)

Musk already flatly denied that he had ever been "cleared" by Tesla for the next leg of the journey. Somebody's wrong.

> The final leg of his trip was 61 miles and yet he disconnected the charge cable when the range display stated 32 miles. He did so expressly against the advice of Tesla personnel and in obvious violation of common sense.

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Re:That Tesla Data: What It Says and What It Doesn’t by jacquesm on Thursday February 14, 2013 @07:19PM (#5223598)

It would be interesting too to see the rates of power consumption for the model S at cruising speed and the 'heat on low'.

From what I remember (doing some electric car design a long time ago) a car that is cruising at about 50 miles per hour uses < 10KW, and that was 1980's car, I'd expect the Tesla to do a little bit better than that.

> If it turns out Tesla denies telling him how he can condition the battery, that would be significant.

It would be, and on top of that they could prove in a re-run that that was what did in the trip (and starting out on a leg with less range than the leg was long, that bit did not make sense at all in the previous article).

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Re:That Tesla Data: What It Says and What It Doesn’t by danielweber on Thursday February 14, 2013 @09:02PM (#5223996)

A Tesla gets between 3.5 and 4.0 miles per kWh[1] at 55mph. That means in an hour they'll use 13.75 to 15.62 kWh.

[1] Doing math for range / capacity at http://www.teslamotors.com/models/options

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Re:That Tesla Data: What It Says and What It Doesn’t by baddox on Thursday February 14, 2013 @08:00PM (#5223791)

Don't worry, I'm sure Musk has the phone calls recorded as well. We'll hear soon.

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