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These batteries store energy by using it to pump lithium ions from the cathode to the anode. Another way of storing this energy would be to pump water from one bucket to another at a higher level. Over time some of the water will evaporate and you will be able to store less energy. In the...

Have to agree with that. Keeping the cable off the floor is a plus for certain.

I suppose the answer will depend on the wall "charger" make and model but none that I have seen make any electrical connection between the charging wand and the "holster". The holster is a purely mechanical holder for the wand. Thus it makes no difference whether the wand is in the holster, on...

I should add that you can change the charging rate (current) during a charge session in which case the answer is broadened to say that the plot follows your rate requests throughout the charge. Desired rate can be set in either in the car or via the app. Per the discussions here you will...

I found a spec sheet for a 2170 cell with capacity 4 Ah and average operating voltage of 3.65V. At this voltage it stores 14.6 Wh and one wold need, therefore around 13,700 of them for a 200 kWh battery with the actual number dependent of what values of P and S work out to be. The internal...

We can WAG it. At 240V 30A is 7.2 kW. 90% charging efficiency means that 6.48 kW is delivered to the battery and in 8 hr it would receive 51.8 kWh. Deduct 2kWh phantom drain from that to get around 50 kWh. Since this is a TriMotor its battery is going to be about 200 kWh meaning this 50 kWh...

In non equation form a linear dependence between x and y would be expressed as something like "y depends on the first power of x multiplied by a constant plus another constant." But no one would say that. They'd simply say "y is linear in x" or "y is a linear function of x". People who paid...

I would be happy to except that I didn't write any formulas. You show me a formula that can be graphed and I'll happily graph it for you but there simply aren't any formulas in these posts! Just so you know what a formula looks like y = m*x + b would be one. A graphable formula has a...

Referring to the first quote: How do you graph a curve as a straight line? Referring to the second quote graphing 5C, C/5, 2C and C/2 would result in sets of 4 points parametric in C. How do you get a razor line out of that? I've been dealing with linear equations since high-school and I've...

But I never said anything about a linear formula. Can you please tell me where you think I did?

You must have some very strange notion as to what "linear" means.

We aren't talking about charging cars. We are talking about the things that effect battery longevity and proposing gedanken experiments to give us insight. I'm afraid we are discoursing on very different planes. Don't know what you are talking about here. In a test protocol the current would be...

Call it what you will. The intelligent individual will respond to the question by saying to himself "Of course not - but those charge/discharge rates are absurd." But he will also understand where the instructor is going and, we hope, ask himself "Well how about 5C and C/5 or 2C and C/2?"

Well yes there are standards for example the IEC standard I mentioned in my last post but they aren't often (that I have seen) referred to. For example when Tesla promises the "million mile battery" they don't put in the footnotes that it's that with respect to IEC - xyZ45 Rev.B. This is why, as...

Yes, and now the the bottomless font thereof has just given us some more. No, a cycle is NOT any equivalent usage then adds up to 100%. A cycle is whatever the standards body that defines what a cycle is says it is. An academic paper reporting on degradation vs cycles will usually specify...

I wouldn't. I'm just pointing out that the "cycles" specs given for many batteries does not, by any means, give the complete story. I was trying to make a little joke. You said my Powerwall batteries didn't ever cycle because they never dip below 50% and I was pointing out that they would...

That's really good news because the batteries in my Powerwalls never go below 80% and thus never complete a cycle meaning that they will never reach their rated cycle spec and never need to be replaced! But clearly that's not the case. After 10 years they will hold appreciably less charge than...

It just occurred to me that an important aspect of the answer to that question is Tesla's new policy of NOT including a UMC with its vehicles any more so that if you don't have EVSE set up at home you will not be able to charge at home from any outlet in your house be it 120 or 240. Keep this in...

I would hardly call it "solid" but the specifications for the UMC indicate the number of miles added per hour of charging and the current drawn from each of the UMC configurations. These numbers suggest that the 120V configuration would require 25% more power. It's relatively easy to measure...

I know your time is valuable but we don't want all this wrong information staying out there so again I ask you to pick just ONE thing that is incorrect and see if we can't correct it. We'll work them off one at a time.