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NiMH batteries use expensive nickel and misch metal for the cathode and anode, respectively.
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No big deal. In production for automotive volume, materials cost isn't near as much as assorted manufacturing costs.
In the 1990s, ECD Chairman Robert Stemple quoted $150/kWh in volume for 20,000 electric cars a year for the large AH Ovonics. More recently, Team Fate at UC Davis claims to have contacted experts on this battery, $200-300/kWh today in the same volume.
Further, nickel is much more plentiful than lithium. The known commercial reserves are 62,000,000,000 kg of nickel(USGS). 5,000,000,000 kg is produced each year. You need about 7 kg of nickel for each kWh of battery.
We have about 10,000,000,000 kg of Lithium(DNPM.gov). Each kWh of battery needs about 2 kg of lithium.
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Lithium batteries will (eventually) get very cheap because they don't need many grams of lithium for the anode for a given output. The newer iron phosphate cathode materials are dirt cheap.
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Hopefully they will get cheap. What we need isn't cheap materials, but large scale modules that are sufficiently safe so that cost per kWh in mass production can decline and lessen the need for a complicated management system.
Nickel batteries are there. But the oil companies have the patent on large scale Ovonics. 18650-size Lithium batteries would be $250-500/kWh in automotive volume(AC Propulsion). So per kWh, nickel would likely be a bit cheaper in mass production.
Further, the world's lithium reserves won't be able to run as many cars as its nickel reserves.
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Lithiums have much better energy and power density than NiMH batteries. So, hybrids and PHEVs are eventually going to use lithiums.
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Only so much lithium to go around.
Any sustainable future that does not involve stripmining the Earth bare will require use of multiple chemistries in both hybrids and pure EVs. If we stick to one chemistry, there won't be enough resources to go around. To me, the best route looks to be a combination of LiIon EVs, NiMH EVs, and PbA EVs and also hybrids using a wide array of chemistries. Firefly's lead acid batteries apparantly have specific capacity exceeding that of NiMH.
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NiMH batteries will be consigned to the dustbin of history, much like the Edison cell.
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Much like the Edison cell, Ovonic batteries last ****ing forever!
Cobasy's very conservatively rates them to 1,200 cycles to 80% discharge, Team Fate at UC Davis claims 1,750 cycles to 100% discharge. Today's lithiums get around 400-500 cycles to 80-100% discharge.
It is unknown how long lithium batteries will last in a vehicle application, but the general consensus is 100,000+ miles until 80% of usable capacity is remaining with proper temperature management. Lithium battery capacity can rapidly degrade if the batteries are left to sit unused. NiMH batteries in electric Toyota RAV4s owned by Southern California Edison have exceeded 150,000 miles, still going strong after 10 years with no capacity or power loss yet. Southern California Edison has had only 6 module failures in over 3,000,000 miles of fleet use. Other RAV4 EVs simply haven't been driven enough to accumulate that number of miles. Many RAV4 EV users suspect their packs may last over 250,000 miles.
Would someone be able to wrestle control of large AH NiMHs from the oil companies and mass produce them, they would likely last much longer than Lithium Ions and be far cheaper per mile for use in a vehicle than LiIon. NiMH doesn't need as complex of a management system as LiIon when used in large AH modules, helping drastically reduce mass production costs. NiMH can also create much more kWh for EV battery packs than LiIon given usable world reserves of these resources. These benefits come at the expense of range and horsepower compared to lithium. But even with sufficient aerodynamics, EVs can do comparable range to gas cars on NiMH. The Solectria Force(a converted Geo Metro sedan) entered in the Tour De Sol did 200-250 miles per charge at highway speeds. The Solectria Sunrise can do over 300 miles per charge at highway speeds(Did 373 miles per charge in a Tour De Sol run in 1998).
I don't think it would be wise for EV producers and hybrid producers to put all their eggs in one basket. Someone needs to tell Chevron-Texaco that they can go **** themselves, and defy their legal reigns on that patent, and then REFUSE to pay any fines in court. A Chinese automaker would be in a great position to do this.