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26-second charging of lithium AA battery developed by Shawn West

26-second charging of lithium AA battery developed by Shawn West

Just saw this news. Can any engineers comment on its applicability to Tesla's battery charging? Thanks.

http://recombu.com/mobile/news/battery-technology-fully-charged-in-26-se...

hpjtv | 7 augustus 2014

Sounds like a good idea. Basically a capacitor in series with a voltage regulator/current limiter. You charge the capacitor directly with a higher voltage and set the voltage you need through the regulator. Hopefully it works as well as the developer says it should.

Remnant | 7 augustus 2014

It looks like Tesla should promptly verify the claim and, if affirmative, hire the the guy to apply it to the Tesla batteries.

Anemometer | 8 augustus 2014

looking at the pic.. if that is the solution stick a big capacitor inside an aa cell case and use an ic to level the output power, i'd ask these questions
1) what charge does it hold .. in mAh
2) how long for.. in days
3) what rate can it deliver power at in mW and at what voltage
4) at what cost

im sure it works in some sense but it can fall short of chemistry.

capacitors arent known for holding charge over long periods. but they are good for balancing power over short periods. I'd have thought a charge would only take 1 second ;)

Brian H | 8 augustus 2014

Buffering batteries with supercaps was an early enthusiasm of Elon's. But he found that bigger batteries took power fast enough, and didn't require the volume of 'caps, while providing range and sustained power they couldn't. There was no 'intersection' where the trade-off of giving up sustained power for charging speed made sense.

Boukman | 8 augustus 2014

If this actually works, He should send a prototype to EM asap...Then he would not have to go to kickstarter for I am sure Telsa would give him a full lab with a salary to boot...Ahh... Charging a MS/MX to full capacity in 5/10 minutes...plus a 500 miles range... EV heaven...I can't wait!

Dramsey | 8 augustus 2014

It wouldn't make that much difference, since it would be practically impossible to deliver that kind of current to the giant Tesla battery pack.

Take the standard 120kW Supercharger that can give you 170 or so miles of range in 30 minutes. Now say you have a new magic battery pack that can be charged, say, six times faster so it only takes five minutes.

Now you need 120x6 or a 720kW Supercharger. The cable to your car would need six times the cross-sectional area, as would the cables inside the car. You probably wouldn't be able to lift it to plug it in.

Let's not even think about how much power would have to be going INTO the Supercharger. I doubt any location could support it.

Car t man | 8 augustus 2014

You recharge supercaps from supercaps recharged over a longer period of time.
So you charge supercaps with 135kw...

But this thing with supercaps for large capacities won't work at this time.

Red Sage ca us | 8 augustus 2014

FYI... I'm pretty sure the battery pack that Tesla uses has rather hefty capacitors as part of its electronic control system.

Brian H | 9 augustus 2014

RS;
On the other hand, not. Caps, super or otherwise, are BIG. As in cubic volume. There ain't no room in the car for "hefty".

Timo | 13 augustus 2014

High voltage, low farad ones. No need to store the energy.

Haeze | 13 augustus 2014

@Dramsey
Those are just other problems that can be engineered around.

As for the cable to connect to the car for charging, all they would have to do is design a motorized connector that you drive the car over, and it connects directly to the pack from contacts under the car. Then you can make the "Cable" a solid chunk of copper a foot in diameter if you really wanted to.

As for the public supply not being able to sustain that much power, that is where stationary storage would play a big role. Have a bank of capacitors and batteries that charge from the grid, and solar panels located at the Supercharger. In the time between cars being parked at the charger, the grid tops them back off at its lower voltage/amperage. Essentially, filling up a local reservoir of power slowly, while the cars take power from the reservoir at a high rate, but for very short bursts.

Timo | 14 augustus 2014

Capacitors are not needed in stationary storage, just big ass battery that preferably has low self-discharge rate. Can be cheap too, doesn't need to be li-ion, lead acid is good enough

Remnant | 14 augustus 2014

@ Timo (August 14, 2014)

<< Capacitors are not needed in stationary storage, ... >>

It seems West's cicuitry raises the voltage during the recharging process then lowers it back to the nominal level for stationary storage and discharge use.

It might be worth verifying this claim both on single cells and on battery set.