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One of the reasons for the moon project was to beat the Soviet Union. There was no telling at the time what one could do with the moon as a base, and we didn't want to chance them getting a space foothold that could wipe us or our missles out without adequate warning.
Let alone the potential reconnassance I might have provided.
 

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Well after I got my newsletter from Toyota telling me the winner is ..... LiIon, I wasn't surprised. More voltage to play with than any nickle based battery. I am not surprised they are developing a prismatic battery type. Heck if you are going to go big might as well design it for use on other things besides cars. Nice thing about LiIon is they can practically mold it to fit anywhere.

Of course to really save money and recoup their investment, they might just put in a smaller battery and switch out just the battery management module. The HSD is quite modular in design which they emphasized over and over again when advertising HSD II in the 2nd Gen Prius. From the sounds of it they only need to run the ICE for about 5 minutes to charge the battery to 85%. No wonder they may use a bigger ICE, bigger means faster heating of critical pollution control elements. And it sounds like they are expanding their battery DOD range from the current 40% - 80% up to 30% - 85%, a little over 37% increase. Wow, they must have a lot of confidence in this new battery!
 

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Toyota and GM slow going

Let's examine the introduction of a new battery technology into Hybrids from the economic/engineering approach. Assuming you have 100,000 production vehicles per year and that the vehicle batteries must run for 10 years with 2 hours of drive time a day. This is a total battery run time of 730 MILLION Hours. Now due to warranty costs and ensuring that the car is not priced out of the market, the total complete failures must be about 100 or less. (The "fatal failures" MTBF is vastly more restrictive.) Many more failures, the vehicle becomes known as a lemon and the resulting cost to fix, repair, recall makes the whole line unprofitable. Think "Yugo redux". This puts a hard requirement of a Mean Time Between Failure (MTTF) of about 7 million hours for a hybrid car battery (Engine numbers are very similar). Until this level of battery maturity is reached in production, the capacity and capability of a sexy new battery technology is meaningless. Yes, niche manufactures can tolerate a higher failure rate, but the 100,000 car a year manufacturers cannot. This is the hurdle that is being worked hard.

As a personal note, of all the car problems of many years, it was a battery explosion in my Camry while starting the car that scared me the most. (Internal short due to a seperator manufacturing defect.) These new batteries extremly high energy storage densities will make that explosion look like a small firecracker, unless the engineering is unbelivably good. One last note, unlike a gas fire which can burn long and hot, a battery energy release is over in a fraction of a second. We need the new batteries....but they need to be super safe.
 

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I agree about the required reliability. And they need the ability to keep consistency in their manufacturing process to maintain their required reliability target.

As far as your battery problem, that only happened because the hydrogen gas produced by the lead-acid battery was ignited by your short circuit. And regular lead-acid batteries are not sealed (hermetically) so they have quite an air gap between the electrolyte and the top of the battery. This allows for a gap for the spark/arc to form. These gaps aren't in NiMH or LiIon. However, they can be shorted externally and be made to rupture. Typically this is the reason why their terminals are protected and/or sealed. Lithium based batteries are a little harder to make explode because they can't dump enough current due to their high internal resistance (i.e. why they are 3V per cell). Older Lithium based batteries would rupture (not explosively) and the electrolyte would start to oxidize (burn) when exposed to the air. Newer Lithium batteries don't have this problem.

Sorry if that was a little long winded to try and tell you Lead Acid batteries are quite a bit more dangerous than the Nickel or Lithium based batteries.
 

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I don't believe lithiums have higher internal resistances. Voltage has nothing to do with internal resistance, it is based on the chemistry.
 

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Has almost nothing to do with chemistry. Has everything to do with how they are manufactured. Otherwise they wouldn't be able to make 1.5V AA Lithium based batteries.

Typically Lithium based batteries use many more separation layers between multiple cathodes and anodes. Which is why they are so expensive to make. And of course more separation layers = more resistance. To the tune of an order of magnitude over lead-acid and nickel. Of course nano-technology may change things in unexpected ways, so I can't say this won't change. Another reason the fuel cell industry is having a tough time against the battery industry.
 

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Ahh-Intelligent comments. It's not long winded when facts are discussed. You are really addressing the core issue, how to take the limitations of any battery chemistry and engineer packaging/suppression techniques. Submarine batteries have very, very safe Lead Acid batteries with the H2 monitoring, gas sensors, dual compliance casing technology etc....but these are specific to Lead Acid and do not make economic sense in cars. With the advent of an unbelivably large battery market in cars, there should be an incredible push to evolve BIG batteries on the part of the battery manufacturers. However, it is the car makers that are having to carry the load here. Tesla motors had to fight the inertia of their LiIon suppliers who were more worried about the legal aspects than the HUGE market available for hybrids and electric cars. Likewise, Toyota had to take partial ownership of Panasonic to ensure the focus on car battery specifics rather than consumer trinkets. GM is doing something smart (but for how long?) by getting two big battery manufacturers supplying the Volt.
 

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Any two metal pairs in an electrolyte will always yield the same voltage. It can be chemically shown that this happens. This was even shown to us in high school. Ever notice that NiCd always gave 1.2V instead of the standard 1.5V given by zinc/carbon and alkalines? Now one can stack cells to make a higher voltage battery, and yes the quality of the connections and how you prevent coatings of the electrodes as the battery gets used up will affect internal resistance.

By the way, internal resistance itself does not determine the battery's voltage. It does determine how much the voltage drops as you pull more current out of the battery. V=IR. If the internal battery is 3V, and the internal resistance is 1 ohm, you'll lose 1 volt when you draw 1A since with V=IR, V=1*1=1, one volt drop across the internal parasitic resistor. If you used a very high impedance voltmeter, you'll see the full 3 volts.
 

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HI All...

This is the latest release from TOYOTA about their Hybrid Battery Bind.

Toyota Motor Corp. is facing a problem carmakers would like to have. The world's leading carmaker is struggling to keep up with the demand for its hybrid vehicles.

That is why it looks like Toyota will also buy hybrid-car batteries from Sanyo Electric Co. Toyota now buys its batteries from Panasonic EV Energy Co, a joint venture with Panasonic Corp. In the coming months, Panasonic plans to take control of Sanyo and continues to await regulatory approval.

Demand for gasoline-electric vehicles continues to surge in Japan, helped by tax breaks and subsidies under a government initiative to promote fuel-efficient automobiles. The problem: Production of hybrids suffers from a supply bottleneck for batteries, Toyota official said.

Right now customers placing orders for a Prius have to wait about eight months before delivery.

In addition to the Prius, Toyota said in its first month of offering it to the public, it had received about 10,000 orders for the Lexus HS250h sedan, the premium brand’s first dedicated hybrid car. The goal was to sell an average 500 units a month.

Toyota will first use Sanyo’s lithium-ion batteries starting in 2011.

The goal is for Toyota to procure about 10,000 battery units per year from Sanyo, the world’s biggest rechargeable battery maker. Toyota aims to sell at least 1 million hybrid vehicles a year in the early 2010s.

Panasonic EV Energy has said it plans to double battery production capacity to around 1 million units a year by the middle of 2010.
 

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Change to an insufficient hits on Hydrogen Ion, someplace many metals can be used as one of the conductors, including nickel. I believe Lithium is the more common one, if the ion is hydrogen.
The problem with Nickel is that the reserves are depleting, thus Nickel is going up in price.


PREVENTATIVE VEHICLE MAINTENANCE
 
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