DIY Supercharger

[Rocky_H]

It’s just to see if I can build a DC charger

This part is an expensive learning project--tinkering, as you described it.

to get energy from solar or off-peak grid stored and then dumped.

This part definitely doesn't need the multi-thousand dollar boondoggle of building a DC charger. It can be done much more simply and cheaply with readily available equipment to have a battery system with inverter to create an AC circuit that can then use the normal charging equipment.

 

[Big Earl]

Exactly. I admire your goals of trying to use solar energy, but the better return on investment would be ditching your idea to "dump" power quickly into your car, and instead focus on powering your home from solar and perhaps also charging the car from solar through the normal AC charging equipment. The "dump" part is where things get very expensive, very quickly.

 

[Whtrbt7]

This part is an expensive learning project--tinkering, as you described it.

This part definitely doesn't need the multi-thousand dollar boondoggle of building a DC charger. It can be done much more simply and cheaply with readily available equipment to have a battery system with inverter to create an AC circuit that can then use the normal charging equipment.

Yes, I’ve set up solar arrays before (and got shocked once =} ). It’s actually not too expensive and I get supplied industrial grade gear from China. I normally use lead acid batteries for small scale arrays and the Chinese have a Li-ion battery/inverter/controller wall unit that makes wiring easy. The storage is 100kWh so it’s large enough for a car. The question is to get it to dump from the battery to the car fast enough.

 

[Whtrbt7]

Exactly. I admire your goals of trying to use solar energy, but the better return on investment would be ditching your idea to "dump" power quickly into your car, and instead focus on powering your home from solar and perhaps also charging the car from solar through the normal AC charging equipment. The "dump" part is where things get very expensive, very quickly.

Yes, I agree. It’s not too difficult to set up a home solar array to use within the home. The capex for such a project is normally in the $20-30k range for the industrial equipment although sometimes less. Things get more dangerous when dealing with high voltage DC. It would be interesting to see if it can be cobbled together with different parts.

 

[e645824]

There are two fast ways to get power into a Tesla. (1) you could kludge something together and directly feed into the DC port and hope that the battery doesn't explode (even SuperChargers have DC-DC converters to control the charging process), or (2) power some rollers that would spin the wheels (dynamometer style) to put energy into the vehicle via the regen system. Like charging the battery on a down-hill slope.

A full Tesla battery pack is around 80 kWh = 288 mega joules. A stick of dynamite is roughly 1 MJ. So a full Tesla battery is 288 sticks of dynamite. Probably not something to play with lightly.

Scott

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MYLR | Red ext | White int | 19" | 5 seats | tow | no FSD | made/delivered Oct 2021

 

[ElectricIAC]

There are two fast ways to get power into a Tesla. (1) you could kludge something together and directly feed into the DC port and hope that the battery doesn't explode (even SuperChargers have DC-DC converters to control the charging process), or (2) power some rollers that would spin the wheels (dynamometer style) to put energy into the vehicle via the regen system. Like charging the battery on a down-hill slope.

A full Tesla battery pack is around 80 kWh = 288 mega joules. A stick of dynamite is roughly 1 MJ. So a full Tesla battery is 288 sticks of dynamite. Probably not something to play with lightly.

Scott

View attachment 841038
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MYLR | Red ext | White int | 19" | 5 seats | tow | no FSD | made/delivered Oct 2021

Regen would eventually quit. I’ve seen it on long downhill grades.

 

[Whtrbt7]

There are two fast ways to get power into a Tesla. (1) you could kludge something together and directly feed into the DC port and hope that the battery doesn't explode (even SuperChargers have DC-DC converters to control the charging process), or (2) power some rollers that would spin the wheels (dynamometer style) to put energy into the vehicle via the regen system. Like charging the battery on a down-hill slope.

A full Tesla battery pack is around 80 kWh = 288 mega joules. A stick of dynamite is roughly 1 MJ. So a full Tesla battery is 288 sticks of dynamite. Probably not something to play with lightly.

Scott

View attachment 841038
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MYLR | Red ext | White int | 19" | 5 seats | tow | no FSD | made/delivered Oct 2021

Ok, so stock up on explosives, check.

 

[Darmie]

Just make one of these and charge the battery off of solar when you can. If it's truly dc to dc you are searching for, then the urban superchargers may work out better than a 150 or a 250 version.

Tesla deploys new mobile Supercharger powered by Megapack instead of diesel generators

Tesla appears to have designed a new version of its mobile Supercharger station that it deploys when traffic significantly increases,...

electrek.co

 

[ElectricIAC]

Just make one of these and charge the battery off of solar when you can. If it's truly dc to dc you are searching for, then the urban superchargers may work out better than a 150 or a 250 version.


View attachment 841174

Tesla deploys new mobile Supercharger powered by Megapack instead of diesel generators

Tesla appears to have designed a new version of its mobile Supercharger station that it deploys when traffic significantly increases,...

electrek.co

Ive seen these at St. George.

 

[avs007]

So Bjorn had a video where he was at Nokian testing winter tires... And while there, he was talking about the DC charger they had there. I think it was a Chempower unit, but it was basically what you described... It connected to AC, tho in this case I think it was 3 phase AC. But anyways, it was able to provide 14 or 16kw DC charging... (I forget the exact number, for simplicity sake, lets say 16). He pointed out the problems with this... He said even tho on paper, 16kw sounded great compared to regular AC home charging... He showed that the Tesla was pre-programmed so that when you connect it to a DC charger, it will always try to precondition the batteries... So in this case, he plugged into the 16kW charger, and he showed that it was using about > 8kW just to warm the battery, and showed that only 7kW was going into the battery. He was saying that his regular home L2 charger actually sent more juice to the battery. He said it would be nice to be able to disable warming that battery, if the DC charger is relatively low power like this, but you cannot... Granted, he did say that after the battery warms up, then the full 16kw would go to the battery. But since they were in the far north, and they were hammering the car during testing, it would not usually send more than 7kW into the battery, since the car would end up sitting in the cold for long stretches.

So with all this being said, I guess my point is that, that you should look at the cost-benefit to all this, becuase it sounds like it's pretty expensive to get a DC charger setup at home, but it won't actually charge your car that much faster than a regular L2 charger.