Battery Experts Seek Lower Costs, Better Technology

The range on weight is typically 3-10 kw/kg, so if you want a 177 kw (ts040) super cap it will weight between 18kg-60kg. Toyota is probably using something around 30kg. That weight for a 60kw supercap even at the high end is only 20 kg is not so bad make a ultra battery with that cap and the current nimh battery, to say add another mg to a prius rear axle, and may make up for the motor/controller/inverter supercap weight in extra capacity for regen braking. The supercap takes up much more room than a lithium battery, but that can be solved by having both (battery for energy, cap for power). The bigger problem is cost as you require more complicated electronics than for lithium and cost/kw is higher than lithium. In racing cost/weight/volume is not a factor as they have mandatory car weights, plenty of room, and plenty of money, so the supercap is superior. Porsche has gone with batteries that although technically are not as good for the application, it is what they are using in their production plug-in hybrids, and hope to use racing to develop better ones.

 

All very exciting stuff to say the least! But it sounds like a complicated system with higher cost attached to it if it ever becomes a reality for the Supra perhaps? All this is a natural evolution for Toyota's HSD system and eventually setting the stage for hydrogen fuel cell cars.

 

For transportation lithium batteries and supercaps have both been advancing, which means somehow for your regular car including almost exotics like the bmw i8 and porsche 918, lithium is a less expensive technology that does everything the car manufacturer wants.

Part of the hydrogen hype versus plug-ins was that battery costs would not come down and companies worked hard to use very small supercaps instead of batteries. Hyundai was the last hold out, and their currently leased fuel cell has a battery not a supercap. Mazda's very mild system uses an supercap, but its really moving charge to the battery, making an ultra battery. The physical size of supercaps is the main challenge.

Now toyota is not dumb using these supercaps in racing. They have a number of technical advantages if size, cost, and weight are not a problem, and there is no physical law saying we can't make these supercaps as small and as light as batteries. Its all about figuring out the manufacturing, but for today a lithium battery is best for consumer vehicles even for a $800,000 monster like the porsche 918, that could beat many race cars on the track.