Battery technolgyのブログ

Battery technolgyのブログ

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The lithium-ion battery works on ion movement between the positive and negative electrodes. In theory such a mechanism should work forever, but cycling, elevated temperature and aging decrease the performance over time. Since batteries are used in demanding environmental conditions, manufacturers AS10B31 replacementtake a conservative approach and specify the life of most

Li-ion between 300 and 500 discharge/charge cycles.

Counting cycles is not conclusive because a discharge may vary in depth and there are no clearly defined standards of what constitutes a cycle. Read more about What Constitutes a Discharge Cycle?. In lieu of cycle count, some batteries in industrial instruments are date-stamped, but this method is not reliable either because it ignores environmental conditions. A battery may fail within the allotted time due to heavy use or unfavorable temperature conditions, but most quality packs will last considerably longer than what the stamp indicates.

The performance of a battery is measured in capacity, a leading health indicator. Internal resistance and self-discharge also play a role but with modern Li-ion these carry lower significance in predicting the end-of-battery-life. Figure 1 illustrates the capacity drop of 11 Li-polymer batteries that have been cycled at a Cadex laboratory. The 1500mAh pouch cells for smartphones were first charged at a current of 1500mA (1C) to 4.20V/cell and allowed to saturate to 0.05C (75mA) as part of the full charge procedure.

The batteries were then discharged at 1500mA to 3.0V/cell, and the cycle was repeated.

Although a battery should deliver 100 percent capacity during the first year of service, it is common to see lower than specified capacities, and shelf life may have contributed to this loss. In addition, manufacturers tend to overrate their batteries; knowing that very few customers would complain. In our test, the expected capacity loss of Li-ion batteries was uniform over the 250 cycles and the batteries performed as expected.

Similar to a mechanical device that wears out faster with heavy use, so also does the depth of discharge (DoD) determine the UM09H36 replacementcycle count. The shorter the discharge (low DoD), the longer the battery will last. If at all possible, avoid full discharges and charge the battery more often between uses. Partial discharge on Li-ion is fine; there is no memory and the battery does not need periodic full discharge cycles to prolong life, other than to calibrate the fuel gauge on a smart battery once in a while. Read more about Battery Calibration.
The rechargeable battery created in the lab of Rice materials scientist Pulickel Ajayan consists of spray-painted layers, each representing the components in a traditional battery. The research appears June 28 in Nature's online, open-access journal Scientific Reports.

"This means traditional packaging for batteries has given way to a much more flexible approach that allows all kinds of new design and integration possibilities for storage devices," said Ajayan, Rice's Benjamin M. and Mary Greenwood Anderson Professor in Mechanical Engineering and Materials Latitude E6500 laptop battery Science and of chemistry. "There has been lot of interest in recent times in creating power sources with an improved form factor, and this is a big step forward in that direction."

Lead author Neelam Singh, a Rice graduate student, and her team spent painstaking hours formulating, mixing and testing paints for each of the five layered components -- two current collectors, a cathode, an anode and a polymer separator in the middle.

The materials were airbrushed onto ceramic bathroom tiles, flexible polymers, glass, stainless steel and even a beer stein to see how well they would bond with each substrate.
In the first experiment, nine bathroom tile-based batteries were connected in parallel. One was topped with a solar cell that converted power from a white laboratory light. When fully charged by both the solar panel and house current, the batteries alone powered a set of light-emitting diodes that spelled out "RICE" for six hours; the batteries provided a steady 2.4 volts.

The researchers reported that the hand-painted batteries were remarkably consistent in their capacities, within plus or minus 10 percent of the target. They were also put through 60 charge-discharge cycles with only a very small drop in capacity, Singh said.
Each layer is an optimized stew. The first, the positive current collector, is a mixture of purified single-wall carbon nanotubes with carbon black particles dispersed in N-methylpyrrolidone. The second is the cathode, which contains lithium cobalt oxide, carbon and ultrafine graphite (UFG) powder in a binder solution. The third is the polymer separator paint of Kynar Flex resin, PMMA and silicon dioxide dispersed in a solvent mixture. The fourth, the anode, is a mixture of lithium titanium oxide and UFG in a binder, and the final layer is the negative current collector, a commercially available conductive copper paint, diluted with ethanol.

"The hardest part was achieving mechanical stability, and the separator played a critical role," Singh said. "We found that the nanotube and the cathode layers were sticking very well, but if the separator was not mechanically stable, they would peel off the substrate. Adding PMMA gave the right adhesion to the separator." Once painted, the tiles and other items were infused with the electrolyte and then heat-sealed and charged.

Singh said the batteries were easily charged with a small solar cell. She foresees the possibility of integrating paintable batteries with recently reported paintable solar cells to create an energy-harvesting Studio 1537 laptop batteriescombination that would be hard to beat. As good as the hand-painted batteries are, she said, scaling up with modern methods will improve them by leaps and bounds. "Spray painting is already an industrial process, so it would be very easy to incorporate this into industry," Singh said.

The Rice researchers have filed for a patent on the technique, which they will continue to refine. Singh said they are actively looking for electrolytes that would make it easier to create painted batteries in the open air, and they also envision their batteries as snap-together tiles that can be configured in any number of ways.
"We really do consider this a paradigm changer," she said.

Co-authors of the paper are graduate students Charudatta Galande and Akshay Mathkar, alumna Wei Gao, now a postdoctoral researcher at Los Alamos National Laboratory, and research scientist Arava Leela Mohana Reddy, all of Rice; Rice Quantum Institute intern Andrea Miranda; and Alexandru Vlad, a former research associate at Rice, now a postdoctoral researcher at the Université Catholique de Louvain, Belgium.
The Advanced Energy Consortium, the National Science Foundation Partnerships for International Research and Education, Army Research Laboratories and Nanoholdings Inc. supported the research.
It's getting difficult to overstate the importance of battery technology. Compact, high-capacity batteries are an essential part of portable electronics already, but improved batteries are likely to play a key role in the auto industry, and may eventually appear throughout the electric grid, smoothing over interruptions in renewable power sources. Unfortunately, Inspiron N5010 laptop battery technology often involves a series of tradeoffs among factors like capacity, charging time, and usable cycles. Today's issue of Nature reports on a new version of lithium battery technology that may just be a game-changer.

The new work involves well-understood technology, relying on lithium ions as charge carriers within the battery. But the lithium resides in a material that was designed specifically to allow it to move through the battery quickly, which means charges can be shifted in and out of storage much more rapidly than in traditional formulations of lithium batteries. The net result is a battery that, given the proper electrodes, can perform a complete discharge in under 10 seconds—the sort of performance previously confined to the realm of supercapacitors.

This appears to be one of those cases where applications badly lagged theory. Since lithium ions are the primary charge carriers in most batteries, the rates of charging and discharging the batteries wind up proportional to the speed at which lithium ions can move within the battery material. Real-world battery experience would suggest that lithium moves fairly slowly through most types of batteries, but theoretical calculations suggested that there was no real reason that should be the case—lithium should be able to move quite briskly.

A number of recent papers suggested that, in at least one lithium battery class (based on LiFePO4), the problem wasn't the speed at which lithium moved—instead, it could only enter and exit crystals of this salt at specific locations. This, in turn, indicated that figuring a way to speed up this process would increase the overall performance of the battery.

To accomplish this, the authors developed a process that created a disorganized lithium phosphate coating on the surfaces of LiFePO4 crystals. By tweaking the ratio of iron to phosphorous in the starting mix and heating the material to 600�C under argon for ten hours, the authors created a material that has a glass-like coating that's less than 5nm thick, which covers the surface of pellets that are approximately 50nm across. That outer coating has very high lithium mobility, which allows charge to rapidly move into and out of storage in the LiFePO4 of the core of these pellets. In short, because lithium can move quickly through this outer coating, it can rapidly locate and enter the appropriate space on the LiFePO4 crystals.

The results are pretty astonishing. At low discharge rates, a cell prepared from this material discharges completely to its theoretical limit (~166mAh/g). As the authors put it, "Capacity retention of the material is superior." Running it through 50 charge/discharge cycles revealed no significant change in the total capacity of the battery.

But the truly surprising features of the cell came when the authors tweaked the cathode to allow higher currents to be run into the cell. Increasing the rate by a factor of 100 dropped the total capacity down to about 110mAh/g, but increased the power rate by two orders of magnitude (that's a hundred-fold increase) compared to traditional lithium batteries. Amazingly, under these conditions, the charge capacity of the battery actually increased as it underwent more charge/discharge cycles. Doubling the charge transport from there cut the capacity in half, but again doubled the power rate. At this top rate, the entire battery would discharge in as little as nine seconds. That sort of performance had previously only been achieved using supercapacitors.

At this point, the authors calculate, the primary limiting factor is no longer storing lithium in the battery; instead, getting the lithium in contact with an electrode is what slows things down. The electrodes also become a problem because they need to occupy more of the volume of the Inspiron 1526 laptop batteryy in order to maintain this rate of charge, which lowers the charge density. That's a major contributor to the halving of the battery's capacity mentioned in the previous paragraph.

A more significant problem is that these batteries may wind up facing an electric grid that was never meant to deal with them. A 1Wh cell phone battery could charge in 10 seconds, but would pull a hefty 360W in the process. A battery that's sufficient to run an electric vehicle could be fully charged in five minutes—which would make electric vehicles incredibly practical—but doing so would pull 180kW, which is most certainly not practical.

It was not until the early 1970s that the first non-rechargeable lithium batteries became commercially available. Attempts to develop rechargeable lithium battery for Pavilion g7 battery followed in the 1980s but the endeavor failed because of instabilities in the metallic lithium used as anode material.


Lithium is the lightest of all metals, has the greatest electrochemical potential and provides the largest specific energy per weight. Rechargeable batteries with lithium metal on the anode (negative electrodes) could provide extraordinarily high energy densities, however, cycling produced unwanted dendrites on the anode that could penetrate the separator and cause an electrical short. The cell temperature would rise quickly and approaches the melting point of lithium, causing thermal runaway, also known as “venting with flame.”


The inherent instability of lithium metal, especially during charging, shifted research to a non-metallic solution using lithium ions. Although lower in specific energy than lithium-metal, Li-ion is safe, provided cell manufacturers and battery packers follow safety measures in keeping voltage and currents to secure levels. In 1991, Sony commercialized the first Li-ion battery, and today this chemistry has become the most promising and fastest growing on the market. Meanwhile, research continues to develop a safe metallic lithium battery in the hope to make it safe.


In 1994, it cost more than $10 to manufacture Li-ion in the 18650* cylindrical cell delivering a capacity of 1,100mAh. In 2001, the price dropped to $2 and the capacity rose to 1,900mAh. Today, high energy-dense 18650 cells deliver over 3,000mAh and the costs have dropped further. Cost reduction, increase in specific energy and the absence of toxic material paved the road to make Li-ion the universally acceptablebattery for 516916-001 for portable application, first in the consumer industry and now increasingly also in heavy industry, including electric powertrains for vehicles.


In 2009, roughly 38 percent of all batteries by revenue were Li-ion. Li-ion is a low-maintenance battery, an advantage many other chemistries cannot claim. The battery has no memory and does not need exercising to keep in shape. Self-discharge is less than half compared to nickel-based systems. This makes Li-ion well suited for fuel gauge applications. The nominal cell voltage of 3.6V can power cell phones and digital cameras directly, offering simplifications and cost reductions over multi-cell designs. The drawback has been the high price, but this leveling out, especially in the consumer market.

The answer is YES. Lead-acid is the oldest rechargeable battery in existence. Invented by the French physician Gaston Planté in 1859, lead-acid was the first rechargeable battery for commercial use. 150 years later, we still have no cost-effective alternatives for cars, wheelchairs, scooters, golf carts and UPS systems. The lead-acid battery for 497695-001 has retained a market share in applications where newer battery chemistries would either be too expensive.


Lead-acid does not lend itself to fast charging. Typical charge time is 8 to 16 hours. A periodic fully saturated charge is essential to prevent sulfation and the battery must always be stored in a charged state. Leaving the battery in a discharged condition causes sulfation and a recharge may not be possible.


Finding the ideal charge voltage limit is critical. A high voltage (above 2.40V/cell) produces good battery performance but shortens the service life due to grid corrosion on the positive plate. A low voltage limit is subject to sulfation on the negative plate. Leaving the battery on float charge for a prolonged time does not cause damage.


Lead-acid does not like deep cycling. A full discharge causes extra strain and each cycle robs the battery of some service life. This wear-down characteristic also applies to other battery chemistries in varying degrees. To prevent the battery from being stressed through repetitive deep discharge, a larger battery is recommended. Lead-acid is inexpensive but the operational costs can be higher than a nickel-based system if repetitive full cycles are required.


Depending on the depth of discharge and operating temperature, the sealed lead-acid provides 200 to 300 discharge/charge cycles. The primary reason for its relatively short cycle life is grid corrosion of the positive electrode, depletion of the active material and expansion of the positive plates. These changes are most prevalent at higherbattery for Pavilion g4 battery operating temperatures. Cycling does not prevent or reverse the trend.


The lead-acid battery has one of the lowest energy densities, making it unsuitable for portable devices. In addition, the performance at low temperatures is marginal. The self-discharge is about 40% per year, one of the best on rechargeable batteries. In comparison, nickel-cadmium self-discharges this amount in three months. The high lead content makes the lead-acid environmentally unfriendly.

ONE of the biggest drawbacks with owning an electric vehicle (EV) is range anxiety - a driver's nagging fear that the battery charge will not get them to their destination. Now IBM claims to have solved a fundamental problem that may lead to the creation of a battery with an 800-kilometre (500-mile) range - letting EVs potentially compete with most petrol engines for the first time.

Standard electric vehicles use lithium-ion (Li-ion) replacement Pavilion g7 battery , which are bulky and rarely provide 160 kilometres (100 miles) of driving before they run down.


A newer type, known as a lithium-air cell, is more attractive because it has theoretical energy densities more than 1000 times greater than the Li-ion type, putting it almost on a par with gasoline. Instead of using metal oxides in the positive electrode, lithium-air cells use carbon, which is lighter and reacts with oxygen from the air around it to produce an electrical current.


But there's a problem. Chemical instabilities limit their lifespan when recharging, making them impractical for use in cars, says physicist Winfried Wilcke at IBM's Almaden laboratories, based in San Jose, California.


So Wilcke studied the underlying electrochemistry of these cells using a form of mass spectrometry. What he found was that oxygen is reacting not just with the carbon electrode, as it was known to, but also with the electrolytic solvent - the conducting solution that carries the lithium ions between the electrodes.


However, if the electrolyte reacts with the oxygen when the car is in use it will eventually be depleted. So, working with his colleague Alessandro Curioni at IBM's Zurich research labs in Switzerland, Wilcke used a Blue Gene supercomputer to run extremely detailed models of the reactions to look for alternative high quality 516916-001 electrolytes. This included a form of atomistic modelling right down to the quantum mechanics of the components, says Curioni.


"We now have one which looks very promising," says Wilcke. He won't reveal what material it is but says that several research prototypes have already been demonstrated. And as part of Battery 500, an IBM-led coalition involving four US national laboratories and commercial partners, the hope is to have a full-scale prototype ready by 2013, with commercial batteries to follow by around 2020.

If it works, this would solve a major obstacle with lithium-air batteries, says Phil Bartlett, head of electrochemistry at the University of Southampton, UK. There are other practical issues to address, such as enabling such batteries to cope with moist air. "Lithium in water spontaneously catches fire," he points out.

Lithium-ion polymer batteries have a high power density that gives you a long battery life in a light package. And you can recharge a lithium-ion polymer battery for 497695-001 whenever convenient, without requiring a full charge or discharge cycle.

Standard Charging


Most lithium-ion polymer batteries use a fast charge to charge your device to 80% battery capacity, then switch to trickle charging. That’s about two hours of charge time to power an iPod to 80% capacity, then another two hours to fully charge it, if you are not using the iPod while charging. You can charge all lithium-ion batteries a large but finite number of times, as defined by charge cycle.


A charge cycle means using all of the battery’s power, but that doesn’t necessarily mean a single charge. For instance, you could listen to your iPod for a few hours one day, using half its power, and then recharge it fully. If you did the same thing the next day, it would count as one charge cycle, not two, so you may take several days to complete a 11.1v 5200mah 9cells Pavilion g4 battery cycle.


Each time you complete a charge cycle, it diminishes battery capacity slightly, but you can put notebook, iPod, and iPhone batteries through many charge cycles before they will only hold 80% of original battery capacity.

Starting (sometimes called SLI, for starting, lighting, ignition) batteries are commonly used to start and run engines. Engine starters need a very large starting current for a very short time. Starting batteries have a large number of thin plates for maximum surface area. The plates are composed of a Lead "sponge", similar in appearance to a very fine foam sponge. This gives a very large surface area, but if deep cycled, this sponge will quickly be consumed and fall to the bottom of the cells. Automotive11.1v 5200 mah 9 cells Pavilion g7 battery will generally fail after 30-150 deep cycles if deep cycled, while they may last for thousands of cycles in normal starting use (2-5% discharge).



Battery technolgyのブログ

Deep cycle batteries are designed to be discharged down as much as 80% time after time, and have much thicker plates. The major difference between a true deep cycle battery and others is that the plates are SOLID Lead plates - not sponge. This gives less surface area, thus less "instant" power like starting batteries need. Although these an be cycled down to 20% charge, the best lifespan vs cost method is to keep the average cycle at about 50% discharge.


Unfortunately, it is often impossible to tell what you are really buying in some of the discount stores or places that specialize in automotive batteries. The golf car battery is quite popular for small systems and RV's. The problem is that "golf car" refers to a size of battery case (commonly called GC-2, or T-105), not the type or12 cells 516916-001 construction - so the quality and construction of a golf car battery can vary considerably - ranging from the cheap off brand with thin plates up the true deep cycle brands, such as Crown, Deka, Trojan, etc. In general, you get what you pay for.


Battery technolgyのブログ


Marine batteries are usually a "hybrid", and fall between the starting and deep-cycle batteries, though a few (Rolls-Surrette and Concorde, for example) are true deep cycle. In the hybrid, the plates may be composed of Lead sponge, but it is coarser and heavier than that used in starting batteries. It is often hard to tell what you are getting in a "marine" battery, but most are a hybrid. Starting batteries are usually rated at "CCA", or cold cranking amps, or "MCA", Marine cranking amps - the same as "CA". Any battery with the capacity shown in CA or MCA may or may not be a true deep-cycle battery. It is sometimes hard to tell, as the term deep cycle is often overused - we have even seen the term "deep cycle" used in automotive starting battery advertising. CA and MCA ratings are at 32 degrees F, while CCA is at zero degree F. Unfortunately, the only positive way to tell with some batteries is to buy one and cut it open - not much of an option.

A battery, in concept, can be any device that stores energy for later use. A rock, pushed to the top of a hill, can be considered a kind ofhigh quality rn873 497695-001 , since the energy used to push it up the hill (chemical energy, from muscles or combustion engines) is converted and stored as potential kinetic energy at the top of the hill.
Battery technolgyのブログ


Later, that energy is released as kinetic and thermal energy when the rock rolls down the hill. Not real practical for everyday use though.


Common use of the word, "battery" in electrical terms, is limited to an electrochemical device that converts chemical energy into electricity, by a galvanic cell. A galvanic cell is a fairly simple device consisting of two electrodes of different metals or metal compounds (an anode and a cathode) and an electrolyte (usually acid, but some are alkaline) solution. A "Battery" is two or more of those cells in series, although many types of single cells are usually referred to as batteries - such as flashlight batteries.


As noted above, a replacement battery for Pavilion g4 battery y is an electrical storage device. Batteries do not make electricity, they store it, just as a water tank stores water for future use.


Battery technolgyのブログ


As chemicals in the battery change, electrical energy is stored or released. In rechargeable batteries this process can be repeated many times. Batteries are not 100% efficient - some energy is lost as heat and chemical reactions when charging and discharging. If you use 1000 watts from a battery, it might take 1050 or 1250 watts or more to fully recharge it.

Comparing various laptop batteries, you may wonder how to choose a good laptop with a good battery. And how to find the battery with the longest life available for your computer. That's need a practical way to contrast them side by side. However, there is an important measurement of WHr(watt-hours) that determines the amount of laptop battery charging. The more WHr, the longer the battery will last between recharges. If your battery can produce one watt of power for 12 hours, then its rating is 12 WHr. Amp-Hours is anotherreplacement HSTNN-CB72 charging measurement. The difference between WHr and Amp-Hours is that the watt as a measurement of power and the Amp as a measure of current.


The laptop battery provides a fixed voltage to your computer, measuring charge in watt-hours or amp-hours are equally valid methods. For instance, if your battery lasts for 20 watt-hours and always provides 10 volts, then it is valid to state your battery's energy storage capacity as 2 amp-hours. Different batteries use different chemicals to store charges. Whether you're talking about the rechargeable or non-rechargeable variety, all batteries work on the same basic principle: They are essentially a canister of chemicals that produce electricity.


For battery life, how long a laptop with a fully charged battery is able to run typical productivity apps, such as Microsoft Office, McAfee VirusScan, Adobe Photoshop and so on. The longest-lasting notebook according to some reports is the Lenovo (IBM) ThinkPad X60s. When configured with the high-capacity battery, its 8 hours, 16 minutes of life can get you through an entire workday. A Fujitsu Q2010 configured with an extended battery can last 7 hours, 38 minutes. The Dell Inspiron E1405 ran for 7 hours, 21 minutes; the Panasonic ToughBook 74 lasted 7 hours, 18 minutes; and the Lenovo ThinkPad R60 went for 6 hours, 25 minutes on a charge. The inexpensive HP Compaq nc2400 also performed well, clocking out after a lengthy 6 hours, 6 minutes.


After you choosing a good laptophigh quality HSTNN-IB72 , you will take care to make your battery life longer. Your laptop battery should never be stored in an area that drops below 50ºF (10ºC) or rises above 95ºF (35ºC); this means that your laptop should not be left in the car or in a storage area that is not climate controlled. Also, for extended storage of six months or more, the laptop battery should be discharged to 50% capacity and removed from the computer; a battery stored for an extended period of time at full capacity may lose the ability to charge fully, while a battery stored in a fully discharged state may never be able to charge again at all.


Modern laptop batteries tend to last three to five hours, depending on the power needs of the computer and the programs the user runs. Few things are as frustrating as when your laptop battery suddenly won't charge fully or stops holding its charge for as long; when this happens, you'll probably want to buy a replacement battery. PAPATEK.COM is your ideal choice.