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To: cuban leaf
I always like to ask the question, how thick would a wire have to be to fully charge a tesla battery in five minutes.

My math is very rusty, but let me take a stab at it.

A Tesla Model 3 has an 82kWh battery pack. For simplicity's sake, round that down to 80kWh.

The size of the wire will depend on the voltage applied, but let's choose 480V for a commonly used voltage.

In order to deliver 80kW of energy in 5 minutes, that's the equivalent of delivering 960,000kW of energy in an hour.

960,000W/480V = 2,000 Amps of current.

So you would need to have a wire capable of providing 2,000 amps at 480V to the car. I can't find an online wire gauge calculator that will work with current ratings that high.

And you would need a charging station capable of providing 2,000 amps of current at 480V, too.

18 posted on 05/19/2021 9:27:35 AM PDT by Yo-Yo (is the /sarc tag really necessary?)
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To: Yo-Yo

Nice work and it looks correct to me.

I am always cautious and skeptical of claims from companies that are looking for investors.

However, there are a lot of smart people pushing for new battery technology as we speak and there have been some promising developments in the past decade. While most of them are based on big promises, we are moving toward much more efficient batteries that hopefully will not rely on lithium and other rare earth metals (cost) with improved capacity.

It will happen eventually. The company that makes the breakthrough will be among the wealthiest in the world pretty quickly. The capitalist incentive in this market is big.


22 posted on 05/19/2021 9:37:59 AM PDT by volunbeer (Find the truth and accept it - anything else is delusional)
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To: Yo-Yo

The modern charge standard is not 480v it’s 800 volts BMW, Porsche, KIA, and VW already have vehicles that can use the 800v standard. To fully charge 82kWh in 5 mins would take 1200 amps DC which sounds like a lot but your avg diesel starting motor draws well over a 1,000 amps at 24v and those cables are air cooled not much thicker than your thumb. The 800v standard uses liquid cooled cables and would be of similar thicknesses. The next standard after 800v will be 1200v DC polycarbonate and silica insulation at those voltages is a few tens of MM thick the plugs are black when plugged in they are fully two-way digital communication for the charger negotiation protocols only when the plug is fully seated and liquids flowing and ground safety verified would current be allowed to flow. The process is an order of magnitude safer than a user manually pouring flammable liquids into an open container hole with vapors leaking out of said opening. It is impossible to be shocked by a DC fast charger the whole cord is off line until a complex handshake happens and if you were dumb enough to pull the plug which is locked in my a magnetic lock I might add in a millisecond the charger senses the break in continuance and cuts off the DC current simply put you cannot be shocked even with willful user error or malfeasance.


35 posted on 05/19/2021 11:03:13 AM PDT by JD_UTDallas ("Veni Vidi Vici" )
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To: Yo-Yo
how much will that tack on to your electric bill?

how much coal, nat gas, nuke, hydro, wind “infrastructure" will be needed to create all that electricity?

43 posted on 05/20/2021 3:24:33 AM PDT by thinden
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