Article: 1000km on a single charge

[cfg83]

Hello -

My co-worker friend found this :

Japanese team sets new standard: 1000km on a single charge

Giving us yet another reason to get behind electric, the Japan Electric Vehicle Club recently exceeded its own Guinness record for longest distance driven without recharging, achieving a staggering 1,003.184 km (or about 623 miles).

The club's Mira EV, a modified Daihatsu Mira, was powered by a Sanyo battery system containing more than 8,320 lithium-ion batteries, the very same kind found in laptop PCs.

Running at a speed of about 40 km/h (or about 25 mph), the team employed 17 people taking turns as drivers during the course of their 27.5 hour effort. It took place at a track in Shimotsuma, in Ibaraki Prefecture.

Seems like a "Tesla-style" drivetrain if they're using laptop batteries. If they get 623 miles at 25 MPH, what would be the range based on normal usage?

CarloSW2

[RobertSmalls]

Originally Posted by cfg83

If they get 623 miles at 25 MPH, what would be the range based on normal usage?

CarloSW2

Much less.

It says here that the road load for a Metro is nine times as high at a steady 65mph than at 25mph. Also, the faster you discharge a battery, the less energy you can extract from it. So... somewhere around 60 miles? That's enough to get from one side of Buffalo to the other and back. I'd love to have that kind of range.

I'm curious, why did they choose 8320 cylindrical cells instead of a few dozen 60Ah prismatic cells? It seems the latter approach simplifies your battery monitoring/management scheme.

[The Toecutter]

Originally Posted by RobertSmalls

Much less.

It says here that the road load for a Metro is nine times as high at a steady 65mph than at 25mph. Also, the faster you discharge a battery, the less energy you can extract from it. So... somewhere around 60 miles? That's enough to get from one side of Buffalo to the other and back. I'd love to have that kind of range.

I'm curious, why did they choose 8320 cylindrical cells instead of a few dozen 60Ah prismatic cells? It seems the latter approach simplifies your battery monitoring/management scheme.

You neglected to include that at 65 mph you would also be travelling a greater distance per unit of time.

If load increases 9 times, then your run time, not distance, is one-ninth.

The range is probably somewhere between 150-180 miles at 65 mph. The 1997 Solectria Sunrise using batteries with half the energy density could do better than that at such a speed.

James Worden, its designer, hypermiled it in the Tour De sol and got 373 miles(previous record), but that was not at a steady 25 mph and included some highway speeds.

[RobertSmalls]

Originally Posted by The Toecutter

You neglected to include that at 65 mph you would also be travelling a greater distance per unit of time.

*facepalm*