The industry is aiming to supply batteries by 2015 that can run for 200-300 km under normal day-to-day conditions. We've proven that that much - and more - is already possible today.
THE Battery Technology Thread (merged)Here is a post
I had a desulfator for every two 6 volt battery and ran it across the twelve volt series, and it seemed to work our batteries didnt seem to age in the motor home after that, but since it takes the same time to desulfate and it dose to sulfate, I just left it hooked up all the time (it takes very little power)
here is something I found.
Excerpt: ... battery sulfation has been with us for a very long time. The problem is that in a typical wet (sulfuric acid) battery, the lead plates want to be exercised. That is, they want to be charged and discharged on a regular basis. If they just sit there, the acid slowly, slowly builds up a film of sulfide that eventually causes the battery to "go weak".
This "weak" has everything to do with the fact that lead sulfide is a fairly good insulator, and as the sulfide layer builds and builds over weeks and months of disuse, the internal resistance of the battery goes up and up.
Finally it gets to the point where most of the voltage of the battery is dropped in the internal resistance of the battery and darned little gets to the point of intended use…like the starter motor. ...
4. There are going to be some batteries that are so far gone that leaving the desulfator on charge for a month will only get you four weeks and change. In my experience with these circuits, if you get the battery right when you notice that it is laboring to turn the starter, you have half a chance to make the desulfation process work. If it is so far gone that it won't even pull in the master switch relay, the odds of being able to save it are slim to none at all. See photo #6 for an example of a battery that will probably never be able to be brought back to life.
5. The sulfation process took weeks or months to develop. The desulfation process will take the same order of magnitude of time. Don't expect to put the battery on desulfate today and back in the airplane tomorrow. I've left batteries on this system for a month before I was happy with the end result.
and a pretty good site:
http://www.dallas.net/~jvpoll/Battery/a ... urvey.html
THE Blackouts/Brownouts Thread (merged)Good chargers will have a way of reducing sulfation, through through techniques such as pulse width modulation (charging in pulses, basically).
To determine what battery and charging approach is best for you, see the Deep Cycle Battery FAQ. I'm currently using AGMs because of frequent, unpredictable travel requirements.
Will conditioners, aspirins or additives will revive sulfated batteries?Most battery experts agree that there is no evidence that conditioners, additives or aspirins provide any long-term benefits for heavily sulfated batteries. Short term gains, if any, are achieved by increasing the acidity (Specific Gravity) of the battery, which could increase the Amp Hour capacity, but also increase the water consumption and positive grid corrosion; thus, decreasing the overall service life of the battery. If a battery will not take a recharge, then it is best to replace it with a healthy battery. This controversy between the additive manufacturers, battery manufacturers, and independent electrochemists has been going on for over 50 years as demonstrated in this AD-X2 Battery Additive, From a Trickle to a Torrent article from the National Institute of Standards and Technology (NIST) Museum.
Batteries could get a boost from an Oak Ridge National Laboratory discovery that increases power, energy density and safety while dramatically reducing charge time.
A team led by Hansan Liu, Gilbert Brown and Parans Paranthaman of the Department of Energy lab's Chemical Sciences Division found that titanium dioxide creates a highly desirable material that increases surface area and features a fast charge-discharge capability for lithium ion batteries. Compared to conventional technologies, the differences in charge time and capacity are striking.
"We can charge our battery to 50 percent of full capacity in six minutes while the traditional graphite-based lithium ion battery would be just 10 percent charged at the same current," Liu said.
Compared to commercial lithium titanate material, the ORNL compound also boasts a higher capacity – 256 vs. 165 milliampere hour per gram – and a sloping discharge voltage that is good for controlling state of charge. This characteristic combined with the fact oxide materials are extremely safe and long-lasting alternatives to commercial graphite make it well-suited for hybrid electric vehicles and other high-power applications.
The results, recently published in Advanced Materials, could also have special significance for applications in stationary energy storage systems for solar and wind power, and for smart grids. The titanium dioxide with a bronze polymorph also has the advantage of being potentially inexpensive, according to Liu.
If silicon particles are used as the basis of the electroactive powder, the battery's anode can hold more ions. But silicon particles swell as the battery is charged, increasing in volume up to four times their original size. This swelling causes cracks in the PVDF binder, damaging the anode. In research published today by Science, the Georgia Tech and Clemson scientists show that when alginate is used instead of PVDF, the anode can swell and the binder won't crack. This allows researchers to create a stable silicon anode that has, so far, been demonstrated to have eight times the capacity of the best graphite-based anodes.
Novel Energy-Storage Membrane: Performance Surpasses Existing Rechargeable Batteries and SupercapacitorsDr Xie and his team have developed a membrane that not only promises greater cost-effectiveness in delivering energy, but also an environmentally-friendly solution. The researchers used a polystyrene-based polymer to deposit the soft, foldable membrane that, when sandwiched between and charged by two metal plates, could store charge at 0.2 farads per square centimeter. This is well above the typical upper limit of 1 microfarad per square centimetre for a standard capacitor.
The cost involved in energy storage is also drastically reduced. With existing technologies based on liquid electrolytes, it costs about US$7 to store each farad. With the advanced energy storage membrane, the cost to store each farad falls to an impressive US$0.62. This translates to an energy cost of 10-20 watt-hour per US dollar for the membrane, as compared to just 2.5 watt-hour per US dollar for lithium ion batteries.
Dr Xie said: "Compared to rechargeable batteries and supercapacitors, the proprietary membrane allows for very simple device configuration and low fabrication cost. Moreover, the performance of the membrane surpasses those of rechargeable batteries, such as lithium ion and lead-acid batteries, and supercapacitors." The discovery was featured in Energy & Environmental Science and highlighted by the international journal Nature.
The research team has demonstrated the membrane's superior performance in energy storage using prototype devices. The team is currently exploring opportunities to work with venture capitalists to commercialise the membrane. To date, several venture capitalists have expressed strong interest in the technology. "With the advent of our novel membrane, energy storage technology will be more accessible, affordable, and producible on a large scale. It is also environmentally-friendly and could change the current status of energy technology," Dr Xie said.
"We can charge our battery to 50 percent of full capacity in six minutes while the traditional graphite-based lithium ion battery would be just 10 percent charged at the same current," Liu said.
Nanoparticle Electrode for Batteries Could Make Grid-Scale Power Storage FeasibleStanford researchers have used nanoparticles of a copper compound to develop a high-power battery electrode that is so inexpensive to make, so efficient and so durable that it could be used to build batteries big enough for economical large-scale energy storage on the electrical grid -- something researchers have sought for years.
In laboratory tests, the electrode survived 40,000 cycles of charging and discharging, after which it could still be charged to more than 80 percent of its original charge capacity. For comparison, the average lithium ion battery can handle about 400 charge/discharge cycles before it deteriorates too much to be of practical use. "At a rate of several cycles per day, this electrode would have a good 30 years of useful life on the electrical grid"
A lot of recent research on batteries, including other work done by Cui's research group, has focused on lithium ion batteries, which have a high energy density -- meaning they hold a lot of charge for their size. That makes them great for portable electronics such as laptop computers.
But energy density really doesn't matter as much when you're talking about storage on the power grid. You could have a battery as big as a house since it doesn't need to be portable. Cost is a greater concern. Some of the components in lithium ion batteries are expensive and no one knows for certain that making the batteries on a scale for use in the power grid will ever be economical. "We decided we needed to develop a 'new chemistry' if we were going to make low-cost batteries and battery electrodes for the power grid," Wessells said.
The researchers chose to use a water-based electrolyte, which Wessells described as "basically free compared to the cost of an organic electrolyte" such as is used in lithium ion batteries. They made the battery electric materials from readily available precursors such as iron, copper, carbon and nitrogen -- all of which are extremely inexpensive compared with lithium.
The researchers need to find another material to use for the anode before they can build an actual battery. But Cui said they have already been investigating various materials for an anode and have some promising candidates.
Stanford University researchers have demonstrated a battery technology that is able to retain 83% of it’s charge after 40,000 cycles. (1 cycle is 1 charge and 1 discharge.) Lead acid batteries only last a few hundred cycles, and lithium-ion 1,000.
Please note that the cycle life of batteries is not the same as their shelf life. Some batteries, such as li-ion self-degrade even when not being used. Lithium-ion batteries would last 19 years if they did not self-degrade, due to the fact that they have a cycle life of 1,000 cycles, assuming that they are cycled once per week.
This new battery technology is similar to lithium-ion batteries but can use either sodium or potassium ions instead of lithium ions. Sodium and potassium are much more abundant and cheaper than lithium.
What the researchers did was start with a pigment called “Prussian Blue,” which is a compound of iron and cyanide, and they replaced half of the iron with copper, then they manufactured crystalline nanoparticles of the compound. Then they coated it on a cloth resembling carbon substrate. Then, finally, they submerge it in an electrolyte solution called potassium nitrate.
The electrodes exhibited 99% efficiency. “You want the voltage you put in during charging and the voltage you take out during discharge to be same,” Cui says. “Compared to any other battery material, this is absolutely the best.”
That doesn't work either. To charge a battery quickly you need high amounts of power from the wall, at these levels it's going to require high voltage and high current. All newer battery materials can do is allow faster charge acceptance at high power levels without suffering internal damage, the power from the wall will still be high. In fact to take advantage of the faster charge acceptance of the batteries the power from the wall needs to be even higher. For example to charge a 30 kWh pack in 6 minutes would take 300 volts at 1000 amps, or 600 volts at 500 amps, not counting losses. Nothing inside a battery can change that.
"We can charge our battery to 50 percent of full capacity in six minutes while the traditional graphite-based lithium ion battery would be just 10 percent charged at the same current," Liu said.
The only problem is, a high-voltage cathode (-) requires a very low-voltage anode (+) — and the Stanford researchers haven’t found the right one yet; and so they haven’t actually made a battery with this new discovery. It’s an awesome battery in potentia. Stanford’s lead materials science engineer, Yi Cui, (who is a bit of a battery whizz), says they have some promising candidates for the anode, though.
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