800 Volt EV's (New Porcshe Concept) vs 400 Volt EV's

[MitchJi]

Hi,

Are 800 Volt EV's a great idea? Are there any substantial disadvantages?
http://www.porsche.com/usa/aboutporsche/pressreleases/pag/?pool=international-de&id=360138

Stuttgart. In presenting the Mission E at the IAA in Frankfurt, Porsche is introducing the first all-electrically powered four-seat sports car in the brand's history. The concept car combines the unmistakable emotional design of a Porsche with excellent performance and the forward-thinking practicality of the first 800-volt drive system. Key specification data of this fascinating sports car: four doors and four single seats, over 600 hp (440 kW) system power and over 500 km driving range. All-wheel drive and all-wheel steering, zero to 100 km/h acceleration in under 3.5 seconds and a charging time of around 15 minutes to reach an 80 per cent charge of electrical energy. Instruments are intuitively operated by eye-tracking and gesture control, some even via holograms – highly oriented toward the driver by automatically adjusting the displays to the driver's position....

It is not just passionate sportiness that makes up a Porsche but also a high level of everyday practicality. Accordingly, the Mission E can travel over 500 km on one battery charge, and it can be charged with enough energy for around 400 km more driving range in about fifteen minutes. The reason: Porsche is a front-runner in introducing innovative 800-volt technology for the first time. Doubling the voltage – compared to today's electric vehicles that operate at 400 volts – offers multiple advantages: shorter charging times and lower weight, because lighter, smaller gauge copper cables are sufficient for energy transport. A moveable body segment on the front left wing in front of the driver's door gives access to the charging port for the innovative “Porsche Turbo Charging” system. Via the 800-volt port, the battery can be charged to approximately 80 per cent of its capacity in around 15 minutes – a record time for electric vehicles. As an alternative, the technology platform can be connected to a conventional 400-volt charging station, or it can be replenished at home in the garage via convenient inductive charging by simply parking over a coil embedded in the floor of the garage from which the energy is transferred without cables to a coil on the car's underbody.

It seems like the 800 volt system could be a big advantage for power. The limitation for Tesla is the amps. By going to 800 volts they could almost double the power. Is this also a performance advantage because at a similar motor kv the gear reduction could be about twice as much? The combination would be massive?

There is also a potentially big charging advantage, but would 800v charging require completely new infrastructure? For example, how hard would it be to set up an 800v car so that it could be plugged into two 400v chargers? How difficult would it be to retrofit existing chargers to handle 800 volt? Would it be just as easy to use two 400v chargers to charge a 400v system at a similar speed?

Am I overlooking any substantial advantages? I don't think the weight or cost savings of being able to use less copper would be substantial advantages, but I could be wrong.

Beautiful car!:

Thanks!

 

[flathill]

The new connector being tested works at up to 1000v/400a gen2

Gen3 will charge a big rig

400v vs 800v doesnt really matter as they are both deadly but at 800v corona discharge can become an issue

For a car with a small 200kWh pack you could have it charge in 5 minutes with a 100v system no problem, just requires more copper. At least you could work on it yourself and be safer in a crash

 

[MitchJi]

The new connector being tested works at up to 1000v/400a gen2

Gen3 will charge a big rig.

What are the new gen2 and Gen3 connectors?

Thanks!

 

[flathill]

http://www.iec.ch/dyn/www/f?p=103:14:0::::FSP_ORG_ID,FSP_LANG_ID:6619,25

 

[wb9k]

The weight advantage is going to be fairly piddly because the wires still need to be fairly heavy. Getting up over 600 Volts, you start to get into a much greater risk of arc flash inside the battery pack. Of course you can pull more power...which enables you to not only go faster, but also to consume more battery per mile, so that's a double-edged sword as well. The fast charging they're talking about is DC. This car can surely still be charged with any everyday level 2 charger if it has the proper connector. The actual battery charger is on-board the car, taking AC power from the charge station. Thus, you can already charge an 800V battery with common level 2 chargers.

 

[The fingers]

Pity the poor fool who tries to hotwire that sucker. :lol:

 

[speedmd]

I guess if you end up sliding off the road and in a lake, you will not need to worry about breaking the glass to get out!