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How can I supercharge, with my own 400vdc battery?

How can I supercharge, with my own 400vdc battery?

If I have a 400vdc 100kWh battery in my garage, how can I talk to my Tesla to tell it to supercharge. Several people say it is a resistor, but I think the is way more communication going on. Maybe the canbus goes to the charge port. Does anyone know how to do this? Obviously the protocols are out there, because 3rd party chargers are doing it.

murphyS90D | 5 dicembre 2019

To charge a 400 volt battery you need a charging voltage that is higher than 400 volts. For example the 12 volt battery has a charging voltage that is normally set at 13.8 volts although it can go as high as 15 volts. I don't know the charging specification for the Tesla battery but supplying it 400 volts is not going to work.

tes-s | 5 dicembre 2019

Get a Tesla CHAdeMO adapter, and build a CHAdeMO charger based on your 400v battery.

TeslaTap.com | 5 dicembre 2019

Well, it's far more complex if you don't want the battery to blow up. In addition, you may need to connect your pack to a cooling system. The battery pack is very carefully monitored while charging and uses a complex tapering curve to ensure battery longevity.

Not sure how you got a pack outside of a car although a few have done this. If you really want to Supercharge, Tesla has sold a Supercharger in the past. They are not cheap, and most houses do not have access to the 3 phase high-voltage necessary to run the Supercharger. At one time it was thought the costs are in the $100K region to buy a Supercharger. I think several were purchased for private use in Jordan.

Jason Huges also pulled apart a battery pack and turned it into his own personal PowerWall, before Powerwalls were actually announced. You might check his site more a few more details: https://057tech.com/solar

Good luck and be very very careful. There are so many ways for this to go wrong and kill you.

Anthony J. Parisio | 5 dicembre 2019

TeslaTap.com,
OP did not say he has a Tesla pack from a car. He wrote he has a 400 VDC pack.

TeslaTap.com | 5 dicembre 2019

You may be right, but OP is not very clear. 400V 100 kW is a very specific size that somewhat uniquely matches the Tesla pack.

Anthony J. Parisio | 5 dicembre 2019

True.

tes-s | 5 dicembre 2019

I still think the best (only?) way to "supercharge" (DC-charge) the car from a non-supercharger source of any type is using the CHAdeMO adapter.

I don't recall anyone posting about DC charging a MS other than with a supercharger or Tesla CHAdeMO adapter. AFAIK, there are no third-party DC chargers or DC charging adapters available for the MS.

Mathew98 | 5 dicembre 2019

Potential Darwinism award candidate.

Some. Guy jumped out of a Jeep Wrangler this summer while I was supercharging in Georgia. He inquired if he could tap into the SC for some free juice by working his magic on a custom L2 converter for an unnamed, short range BEV.

Hmmm, did any part of "Tesla proprietary high speed charging" raise any alarms in his head? Of course not.

milesbb | 6 dicembre 2019

I agree with tes-s, a CHAdeMO adapter would be the interface way to go. In addition the current/voltage from the battery would need to be controlled, the CHAdeMO handshake with the car needs to be replacated. I could not find any off the shelf hardware that would preform this. An alternative would be to install an inverter, say 50 kw and feed an off the shelf 50 kw CHAdeMO charger (DC to AC back to DC). Very expensive way to go, but that is what Tesla is doing with their portable battery superchargers. I suspect setting this system up to charge more than say 10kw would become a very expensive custom system, $20k +-. You are much better off just running an inverter that supplies the car directly with ac through a HPWC. This $2k 10kw inverter may work for you.
https://www.electriccarpartscompany.com/10kW-GW-Inverter

tommie | 7 dicembre 2019

Thanks to those people that understood my question.
I wasn’t trying to charge my big battery, it is fully charged.
I want to supercharge my 2018 MS. With the fully charged 400vdc battery, made with a bunch of 18650 batteries and an Orion BMS2.

At the Tesla Supercharger, I get a max charge rate of 80kW.
That happens only when I reach about 40% charge.
Before and after that the kW charge rate is lower.
I am not trying to charge my car any faster, I just want to match the supercharger rates.

The CHAdeMO might be the way to go.
I just have to get the protocol for the CHAdeMO.
I’ll search for that, thanks!

tommie | 7 dicembre 2019

Thanks to those people that understood my question.
I wasn’t trying to charge my big battery, it is fully charged.
I want to supercharge my 2018 MS. With the fully charged 400vdc battery, made with a bunch of 18650 batteries and an Orion BMS2.

At the Tesla Supercharger, I get a max charge rate of 80kW.
That happens only when I reach about 40% charge.
Before and after that the kW charge rate is lower.
I am not trying to charge my car any faster, I just want to match the supercharger rates.

The CHAdeMO might be the way to go.
I just have to get the protocol for the CHAdeMO.
I’ll search for that, thanks!

TeslaTap.com | 7 dicembre 2019

@tommie - Thanks for clarifying it. From the first post, it sounded like you had removed the battery or created some new battery and was attempting to use it for some other purpose unrelated to a car.

I guess the big question is why you need such fast charging at home? Most of us are fine with 10 kWh charging overnight, which is always enough to fully charge the car. If you are using a car for a taxi or business, I can see more frequent charging may be needed and a faster option would be nice. I think CHAdeMO may be your best option.

You can buy the adapter from Tesla and then you'll need equipment to provide the CHAdeMO power like this: https://www.alibaba.com/product-detail/CHAdeMo-ev-fast-charger-30-50kw_6... The cost is $5500 for that unit. I did not price shop, just picked the first one I found and have no idea of the quality. Note that CHAdeMO, like a Supercharger, requires, 3 phase 380V power. Not sure where you are located, but in the USA, 3 phase power is rarely available at home. If you need to charge at a business 3 phase power is sometimes available. Good luck with your project.