Research has brought about a variety of battery chemistries, each offering distinct advantages but none providing a fully satisfactory solution. With today’s variety of battery types, better choices can be made to suit specific user applications. This paper talks about the recommended battery chemistry for cell phones and two-way radios in terms of energy density, durability and price.

What’s the best battery for cell phones?

Early cell phones were powered with nickel-based batteries but most newer phones are now equipped with lithium-ion. This chemistry is lightweight, offers high energy density and lasts long enough to span the typical life of the product. Lithium-ion contains no toxic metals.
To obtain thin geometry, some cell phone manufacturers switched to lithium-ion-polymer.

This satisfied consumer requests for slim designs. In the meantime, technological advancements also made low profile lithium-ion possible. lithium-ion packs are now available in 3 mm, a profile that suits most designs. lithium-ion has the advantage of lower manufacturing cost, better performance and longer cycle life than the polymer version.

Lithium-ion is a low maintenance battery(dell inspiron 1520 battery apple a1185). No periodic discharge is needed and charging can be done at random. A random charge means that the battery does not need to be fully depleted before recharge. In fact, it is better to recharge before the battery gets too low. Full discharges put an unnecessary strain on the battery. A recharge on a partially charged battery does not cause memory because there is none.

Charging lithium-ion is simpler and cleaner than nickel-based batteries but the chargers require tighter tolerances. lithium-ion cannot absorb overcharge and no trickle charge is applied on full charge. This allows lithium-ion to be kept in the chargers until used. Some chargers apply a topping charge every week or so to replenish the capacity lost through self-discharge while the battery(sony vgp-bpl8 battery) sits idle in the charger. Repeated insertion into the charger or cradle does not damage the battery though overcharge. If the battery is full, no charge is applied. The battery voltage determines the need to charge.

On the negative side, lithium?ion gradually loses charge acceptance as part of aging, even if not used. lithium?ion batteries should not be stored for long periods but be rotated like perishable food. The buyer should be aware of the manufacturing date when purchasing a replacement battery. Aging affects battery chemistries at different degrees.

Counterfeit cell phone batteries (clone batteries)

In the search for low-cost battery replacements, consumers may inadvertently purchase clone cell phone batteries that do not include an approved protection circuit. Lithium-ion packs require a protection circuit to shut off the power source if the charger malfunctions and keep on charging, or if the pack is put under undue stress (electrical short). Overheating and ‘venting with flame’ can be the result of such strain. (See photos of an exploded cell phone with clone battery on charge.)

Cell phone manufacturers strongly advise customers to replace the battery(sony vgp-bpl5a  dell inspiron 6400 battery) with an approved brand. Failing to do so may void the warranty. Counterfeit cell phone batteries have become visible since the beginning of 2003 when the world was being flooded with cheap replacement batteries from Asia.

Cell phone manufacturers act out of genuine concern for safety rather than using scare tactics to persuade customers to buy their own accessories. They do not object to third party suppliers in offering batteries and chargers as long as the products are well built, safe and functioning. The buyer can often not distinguish between an original and a counterfeit battery(vgp-bps9 sony vgp-bps9 battery) because the label may appear bona fide.

Caution should also be exercised in purchasing counterfeit chargers. Some units do not terminate the battery correctly and rely on the battery’s internal protection circuit to cut off the power when fully charged. Precise full-charge termination and a working protection circuit are needed for the safe use of the lithium-ion battery.

What’s the best battery for two-way radios?

Most two-way radios use nickel-cadmium. These batteries are durable and forgiving if abused. But nickel-cadmium batteries have only moderate energy density and are environmentally unfriendly. Environmental agencies have been discouraging its use, especially in Europe. The recommended alternative is nickel-metal-hydride, a battery(HP Pavilion DM3 battery) that has higher energy density and contains no toxic metals. nickel-metal-hydride has been tested in two-way radios for a number of years but the results are mixed. Shorter than expected service life is the major drawback.

For two-way radios, nickel-metal-hydride has a cycle life, which is half that of standard nickel-cadmium. nickel-metal-hydride prefers a moderate discharge current of 0.5C or less. A two-way radio, on the other hand, draws a discharge current of about 1.5A when transmitting at 4W of power. High discharge loads and sharp pulse currents shorten battery life.

To compare the longevity of nickel-metal-hydride under different load condition, a test was carried out in which batteries of the same type were discharged with a DC and digital load. In both tests, the batteries were discharged to 1.04 volts per cell. The DC load was a steady 500mA; the digital load simulated the Global System for Mobile Communications (GSM) at 1.65 ampere peak for 12 ms every 100 ms with 270 mA standby. (Note that the GSM pulse for voice is about 550 ms every 4.5 ms).

With the DC discharge, nickel-metal-hydride wore out gradually, providing an above average service life. At 700 cycles, the battery(hp elitebook 2530p battery) still provided 80% capacity. By contrast, the same battery type faded more rapidly with a digital discharge and the 80% capacity threshold was reached after only 300 cycles. This phenomenon indicates that the kinetic characteristics for nickel-metal-hydride deteriorate more rapidly with a digital than analog load. Although the test was simulating a GSM cell phone, Tetra and other digital two-way radios have similar loading.

Let’s briefly compare the characteristics of nickel-cadmium and nickel-metal-hydride. nickel-cadmium has the advantage of maintaining steady high capacity and low internal resistance through most of its service life. nickel-metal-hydride, on the other hand, starts with good capacity and low internal resistance but the resistance increases after a few hundred cycles, causing the voltage to drop on a load. Even though the energy may still be present, the battery(vgp-bps8) cannot deliver the high current during transmit and the message cuts off. The radio becomes unreliable.

Nickel-based batteries are high in maintenance. Periodic discharge cycles are needed to prevent crystalline formation on the cell plates, also known as memory. nickel-cadmium is more receptive to memory than nickel-metal-hydride because both nickel and cadmium plates are affected by memory.

Nickel-cadmium should be exercised once ever 1 to 2 months, whereas nickel-metal-hydride can get by with a deliberate full discharge once every 3 months. Without proper maintenance, the advantage of nickel-cadmium over nickel-metal-hydride in terms of cycle life cannot be realized.

Lithium-ion has been tested for two-way radios and the results are positive. Substituting lithium-ion with nickel-based will require chargers specifically suited for this chemistry. While nickel-cadmium and nickel-metal-hydride can often share the same charger, lithium-ion uses a different charge algorithm. There is also a cost premium for lithium-ion. Future two-way radios will undoubtedly be fitted with lithium-ion.

Stanford University researchers have made a discovery that could signal the arrival of dell laptop battery that last more than a day on a single charge.

The researchers have found a way to use silicon nanowires to give rechargeable lithium ion batteries–used in laptops, iPods, video cameras, and mobile phones–as much as 10 times more charge. This potentially could give a conventional battery-powered laptop 40 hours of  Dell Inspiron 1520 battery life, rather than 4 hours.

The new batteries were developed by assistant professor Yi Cui and colleagues at Stanford University’s Department of Materials Science and Engineering.

“It’s not a small improvement,” Cui said. “It’s a revolutionary development.”

Citing a research paper they wrote, published in Nature Nanotechnology, Cui said the increased battery capacity was made possible though a new type of anode that utilizes silicon nanowires. Traditional lithium ion batteries use graphite as the anode. This limits the amount of lithium–which holds the charge–that can be held in the anode, and it therefore limits battery life.

Silicon anodes have the “the highest theoretical charge capacity” according to Cui’s paper, but they expand when charging and shrink during use: a cycle that causes the silicon to be pulverized, degrading the performance of the VGP-BPS8 VGP-BPS9 VGP-BPL8. For 30 years, this dead end stumped researchers, who poured their battery life-extending energy into improving graphite-based anodes.

Cui and his colleagues looked at this old problem and overcame it by constructing a new type of silicon nanowire anode. In Cui’s anode, the lithium is stored in a forest of tiny silicon nanowires, each with a diameter that is a thousandth of the thickness of a sheet of paper. The nanowires inflate to four times their normal size as they soak up lithium, but unlike previous silicon anodes, they do not fracture.

Cui said there are a few barriers to commercializing the technology.

“We are working on scaling up and evaluating the cost of our technology,” Cui said. “There are no roadblocks for either of these.”

Cui has filed a patent on the technology and is considering formation of a company or an agreement with a laptop battery manufacturer. He expects the Dell Inspiron 6400 battery  or other laptop battery to be commercialized and available within “several years,” pending testing.

It seems rechargeable battery(Sony VGP-BPS8 battery ) wear out just as fast as the regular alkaline ones. With all of my new gadgets, I need to know: Are rechargeable batteries really worth the extra cash? And are they really better for mama earth?

—Sam, Breckenridge Great question, Sam! The truth is that rechargeable battery(Sony VGP-BPS9 battery ) can be better for the planet and its people, if you use them correctly and if, in the end of their useful life, you dispose of them properly.

I think they are also worth the extra cash if you use them properly and for the right items. Let’s take a closer look at the inner workings of these little power houses to find out why that is.

Regular “disposable” household batteries, like alkaline batteries, rely on a contained chemical reaction between heavy metals that in turn produces electrons, or a charge. The intensity of this electrical charge reduces over time as the metals get “used.” This is why a battery(Dell Inspiron 6400 battery) that stops working in a high-draw device, like a camera, may still work in a low-draw device, like a remote control.

Because of this, many alkaline batteries that are thrown away or recycled actually still have a charge left in them. But that’s not why they are “toxic.” In the old days, alkaline batteries contained mercury and were super-duper toxic. Now they contain zinc, manganese oxide, and potassium hydroxide instead.

Alkaline batteries are definitely less toxic these days, but not entirely benign. The batteries and the heavy metals inside can be safely recycled and kept out of landfills — for FREE in Summit County — at the Frisco or Breckenridge drop-off centers.

Rechargeable batteries are usually NiMH (nickel metal hydride), Li-Ion (lithium ion), or NiCad (nickel cadmium). These batteries use a similar contained chemical reaction to produce the charge, but unlike the alkaline battery(VGP-BPS9 ) reaction, the process can be reversed by applying electricity (on a battery( HP Pavilion DV9000 battery ) charger).

Rechargeable battery(dell inspiron e1505 battery) can be replenished hundreds to thousands of times. That sounds great, but unlike alkaline batteries that have very low “leakage” rates (only about 2 percent a year), rechargeable batteries have a much higher “leakage” rate (some can be 2percent per day!), which is why they seem to die faster in many devices. One way to stop this fast drain is to store recharged batteries in a freezer or refrigerator.

Another way to keep rechargeable batteries longer is to use them in devices that have a quick, high draw (like a camera) rather than a long, slow draw (like a remote control). Also, be sure to use the correct charger for the battery(PA3465U-1BRS PA3591U-1BRS). Some batteries were originally designed to charge slowly, and placing them on a quick charge device can significantly reduce their useful life.

Just like the older generation of CFL bulbs seemed to have lots of quirks (that odd flicker) and die quicker that expected, the older generations of rechargeable batteries were also filled with quirks that have since been fixed.

If you haven’t tried the newer rechargeable VGP-BPL8  , it’s time to give them a try.

There are numerous full kits that come with various sizes of batteries and a charger. But, when they are finally done being revived over and over again, be sure to recycle them — for FREE in Summit County — at the Frisco or Breckenridge drop-off centers.