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Android Users - Coming Soon! - Migrating from aCar 4.8 to 5.0

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Old 08-30-2006, 12:58 PM   #11
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NiMH batteries use expensive nickel and misch metal for the cathode and anode, respectively. 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.

Lithiums have much better energy and power density than NiMH batteries. So,
hybrids and PHEVs are eventually going to use lithiums. NiMH batteries will be consigned to the dustbin of history, much like the Edison cell.
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Old 08-30-2006, 02:25 PM   #12
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When the Li-Ion cells have the charge and discharge ratings that the NiMh have then they will be used but right now they can't be made safely in large ah capacities so they only can connect a lot of little cells together and using additional circuitry to manage them - gets complicated really fast. Some of the larger cell formats don't have the output rating that they claim or are way too expensive.
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Old 08-30-2006, 04:14 PM   #13
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yeah, it's the lithium batteries that are going to be in the new generation prius,

i don't know how they work, or what makes them better than the old ones (NiMH i assume), i have just read a few articles that have made the claims of over 100 mpg.
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Old 08-30-2006, 05:09 PM   #14
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They can be left in any charge state unlike Lead Acid - have a much higher charge/discharge efficiency and with the Titianium Oxide plate coating can handle much higher charge discharge rates than before and will have much higher cycle life but not yet as high as NiMh operating in a narrow charge state. It is the battery of choice mostly because Lithium is the Lightest Metal known (lighter than water) and produces the highest voltage per cell of any metal combination thus requiring less cells to make more voltage.
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Old 08-31-2006, 02:28 PM   #15
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Quote:
NiMH batteries use expensive nickel and misch metal for the cathode and anode, respectively.
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.
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.
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.
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.
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Old 08-31-2006, 02:55 PM   #16
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Yep, yep, all - battery dot com has 18650 li-ion's for ~$600/kwh, and nimh F's for ~$780/kwh. Even at this price gasoline and ICE's are still cheaper at their *size, but all electric allows for more peak power with minimal efficiency penalties/better drivability, as well as much less in the way of GHG and pollutant emissions. I think the best part is that small single occupant vehicles can be easily powered off of a couple solar panels/deep cycle LA batteries, so a consumer could concievably put together small, efficient, transport that's quick and environmentally sound for less than the cost of an Aveo. Here's the Rav4 EV study.

*I think cars are deliberately designed to be large/not aero in order to discourage other drivetrains. Gasoline is only cheap via large scale production, just like batteries are only expensive via small scale.
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Old 08-31-2006, 03:12 PM   #17
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With today's Li Ion battery prices, cost parity between gasoline and electric would be around $3.50/gallon assuming 150,000 mile life for LiIon. With automotive volume to get price to $300/kWh, cost parity drops to around $2.00/gallon.

With NiMH, cost parity would be around $1.20/gallon and lower with mass production to bring price to $200/kWh. In extreme cases, you'd be able to give gasoline away for free and the maintenance cost alone of the gas car would still outweigh everything for the electric.

With today's lead acid batteries and today's conversions, cost parity ranges from $0.60-3.00/gallon depending on vehicle converted, typical discharge depth, and other factors. Electric VW Rabbits built from an Electro Automotive kit achieve cost parity with their gasoline counterparts around $1.50-1.80/gallon, for instance. My electric Triumph is projected to reach cost parity with its gas counterpart at under $1.00/gallon, but I'll wait and see how it really turns out. Lead acid batteries are much more dynamic due to their susceptibility to deep discharges and generally short range.

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*I think cars are deliberately designed to be large/not aero in order to discourage other drivetrains. Gasoline is only cheap via large scale production, just like batteries are only expensive via small scale.
The more simpler, likelier explanation is that less aero drag induced means less power required at speed equates to less engine wear and from that, less maintenance. Auto maintenance is the bread and butter of the auto industry. when GM, Ford, and Dodge were still profitable, aftermarket repairs and services was half of their profit margins. An extremely aero design could have dramatically reduced maintenance costs. The less you spend on repairs, the less money the automakers bring in.

It's not really style that is effecting aerodynamics as many would think. By and large the auto industry still ignores simple advancements like wheel spoilers, bellypans, and attention to the front grill of cars, which would have absolutely no effect on the appearance of the car itself and no significant cost. In order to get these things, you're either getting a Toyota or Honda, or shelling out big bucks for a luxury car.
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Old 08-31-2006, 07:32 PM   #18
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Hey Prius hypermillers! What are the basic tricks to get high mileage in one and anyone ever charge up the battery by down hills?
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Old 08-31-2006, 07:46 PM   #19
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Quote:
Originally Posted by The Toecutter
The more simpler, likelier explanation is that less aero drag induced means less power required at speed equates to less engine wear and from that, less maintenance. Auto maintenance is the bread and butter of the auto industry. when GM, Ford, and Dodge were still profitable, aftermarket repairs and services was half of their profit margins. An extremely aero design could have dramatically reduced maintenance costs. The less you spend on repairs, the less money the automakers bring in.
I'm not sure if that really applies since from what I've "heard", most wear occurs during cold startups, so clocking lots of long highway trips won't result in nearly as much wear compared to twice as any cold starts... As a matter of fact, Toyota's bread and butter engine the 22r seems to run really cool, so the key to engine life back in the 80s may have been minimal changes between cold/operating temperature.
Besides, it;s not like they wouldn't purposefully design parts that failed so they could recall them later, with a "friend" getting the contract. My uncle worked as a tech for Pac Bell, and he would not accept a promotion as manager because he didn't want to have to deal with that BS. Anecdotal obviously, but still I think it's pertinent.
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I think if i could get that type of FE i would have no problem driving a dildo shaped car.
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