Laptop Battery, Ac Adapter, Hard Drive, etc.

A battery-electric vehicle (BEV) uses electricity stored in its battery pack to power an electric motor that turns its wheels. The battery pack is often recharged by connecting or “plugging” it into a wall socket or other electrical source, such as a solar panel. Because a BEV uses electricity as a fuel, there are no emissions out of its tailpipe. In fact, it does not even have a tailpipe! Furthermore, it costs pennies, rather than dollars at the gas pump, to recharge a BEV. The development of BEVs has made a significant contribution to battery research and to the advancement of electric motors and power electronics used in both hybrid electric and fuel cell vehicles. Yet, the widespread use of BEVs depends on advances in battery technology.

Benefits and Limitations

• Pollution. Battery-electric vehicles do not produce any tailpipe emissions. However, many BEVs recharge using electricity generated at power plants that emit global-warming and smog-forming pollutants. When BEVs are recharged using renewable energy sources like wind, solar, or hydropower, they do not cause any air pollution at all. Notably, even if BEVs are recharged with electricity from power plants that use fossil fuels, they are up to 99 percent cleaner than conventional vehicles and can cut global warming emissions by as much as 70 percent.
  
• Cost. Battery-electric vehicles cost significantly more than gasoline vehicles, mostly because their advanced battery packs are expensive to produce—especially in small volumes. Higher purchase prices are partially offset by BEV’s lower fuel costs, which are over one-third the cost of refueling a gasoline-powered vehicle.
  
• Performance and Range. To the driver, a battery-electric vehicle offers a quiet, smooth, and high-performance driving experience. BEVs have range limitations of 50-100 miles per charge depending on battery type and driving conditions. Yet, given that most drivers travel less than 50 miles most days, BEVs could satisfy many driving needs. Sourse: http://www.ucsusa.org
  

Two factors have a significant impact on the purchase decision of a hard drive: drive capacity and performance. Issues such as operating noise, temperature or power consumption are interesting, but usually only of great importance to a limited number of users and applications. 4,200 RPM drives are almost silent, and those spinning at 5,400 or 7,200 RPM generally can only be heard only as long as the CPU fan does not kick in.

Notebook users can choose among lots of different 2.5" drives in capacities ranging from 30 to 160 GB. The selection includes 4,200, 5,400, and 7,200 RPM models, with UltraATA/100 or Serial ATA/150 interfaces. Be careful with ultra portable notebooks, though. Models such as the Dell X1 or Samsung's Q30 family are based on tiny 1.8" hard drives. These require less power and space, but their performance is considerably worse, which you will easily notice in everyday work with such a device.

While most users consider capacity only, we strongly recommend taking a close look at performance parameters as well. Choosing a faster hard drive will make your daily work more pleasant than will having a few extra gigabytes. The somewhat higher energy consumption of faster spinning drives is usually compensated for by finishing read/write tasks much quicker. In the end, the battery run time of notebooks using high-speed hard drives is not considerably less than that of models with slower drives.

Currently, 7,200 RPM drives are available at up to 100 GB, while 5,400 RPM reach all the way up to 160 GB. If you intend to use your notebook intensively, we recommend going for nothing below 7,200 RPM. All other users should select a 5,400 RPM drive; 4,200 RPM models should be avoided as they are slower and at this point, provide little to recommend them.

source: http://www.tomshardware.com/

A motherboard can be defined as a central circuit board creating a complex electronic system from within a computer for example.

A motherboard is vitally important as it provides the electrical links by which the other components of the system talk to each other and also contains the central processing unit, most commonly called CPU and other subsystems such as real time clock for example, and some other secondary interfaces. They are produced in different sizes and shapes which can be specific to each computer maker. Actually, most computer motherboards are now using a standard form since 2007.

Motherboards are most of the time air cooled with heat sinks often installed on larger chips. Most motherboards also have connectors for additional case fans as well just in case. More recent motherboards now have integrated temperature sensors to detect motherboard and CPU temperatures in order to regulate the fan speed and lower the temperature faster and better. This being mainly due to the appearance of thermal management systems that can now cool down the motherboard and reduce the noise more efficiently for better performances. A recent study found that some computer crashes and other general issues like screen image distortions or other errors can actually be attributed not to software or peripheral hardware but to the motherboards. So a better performing motherboard is really essential if you want your computer to work properly and longer.

Laptops would usually use a much different kind of motherboard. They usually are miniaturized and highly integrated motherboards specifically designed for laptops. The fact that they are almost unique is actually one of the reasons why laptops are so difficult to upgrade and repair.

As a matter of fact, Industrial motherboards need to be tougher than normal motherboards found in personal computers or laptops. Being used in tougher conditions than standard computer motherboards, industrial motherboards, like industrial LCD displays or Industrial LCD touch screen need to be able to cope with higher temperatures, need to be tougher in case of a shock or a hit, and need to last much longer, simply because they are intended to provide stable motherboard platforms for industrial users who demand long production lifetimes in extreme conditions. But obviously, a motherboard is not the only component of an industrial computer or other electronic equipment and if the case and the other components are not resistant enough or can not really cope with extreme conditions, everything will break down quickly.

A battery is a device that converts chemical energy directly to electrical energy. It consists of one or more voltaic cells. Each voltaic cell consists of two half cells connected in series by a conductive electrolyte. One half-cell is the positive electrode and the other is the negative electrode. The electrodes do not touch each other but are electrically connected by the electrolyte, which can be either solid or liquid. In many cells, the materials are enclosed in a container, and a separator, which is porous to the electrolyte, which prevents the electrodes from coming into contact.

Each half cell has an electromotive force (or emf), determined by its ability to drive electric current from the interior to the exterior of the cell. The net emf of the battery is the difference between the emfs of its half-cells, as first recognized by Volta. Thus, if the electrodes have emfs and , then the net emf is . (Hence, two identical electrodes and a common electrolyte give a zero net emf.)

The electrical potential difference, or across the terminals of a battery is known as terminal voltage and is measured in volts. The terminal voltage of a battery that is neither charging nor discharging is called the open-circuit voltage and equals the emf of the battery. Because of internal resistance, the terminal voltage of a battery that is discharging is smaller in magnitude than the open-circuit voltage and the terminal voltage of a battery that is charging exceeds the open-circuit voltage. An ideal battery has negligible internal resistance, so it would always have a terminal voltage of . This means that to produce a potential difference of 1.5 V, chemical reactions inside would perform 1.5 J of work for a charge of 1 C.

The voltage developed across a cell's terminals depends on the chemicals used in it and their respective concentrations. For example, alkaline and carbon-zinc cells both measure approximately 1.5 volts, due to the energy release of the associated chemical reactions. Because of the high electrochemical potential changes in the reactions of lithium compounds, lithium cells can provide as much as 3 volts or more.

As you're buying batteries, it's important to find out two things: how long they last and how much they cost. You'll also want to figure out exactly how the battery works with the device, and the length of time it needs to recharge. You don't want to be on a business trip trying to figure out batteries right before a big presentation!

The first rechargeable batteries for laptops were nickel cadmium (NiCd) batteries. They didn't cost much, worked very well and could be used in many different devices. However, as more efficient and lighter batteries have come on the market, many laptop companies have discontinued using NiCd batteries.

Nickel metal hydride (NiMH) batteries, for example, were one better option because they had greater output, cost less, were safer and more reliable. NiMH batteries had one major drawback, though: the "memory effect." Because they had to be fully discharged before they could properly recharge, these batteries were seen as a time-consuming hassle. Older models of laptops may have these batteries.

Lithium ion (LiON) batteries are the standard batteries for most laptops made today. They weigh much less than previous batteries and they don't have the memory effect of NiMH batteries. While they have many advantages, they're also more expensive than other laptop batteries.

While cell phones are getting cheaper these days, they are still a costly purchase. To get the top of the line model you want, it may be necessary to save up. And once you have it, you'll want to stick to a tight budget so you can afford all the monthly charges and extra fees. The cost of high-quality cell phone batteries is another concern to keep in mind.

Most cell phones have a basic battery, but many people choose to purchase a better battery with a higher capacity. Like so many things, the cheapest option may not be the best. As the old saying goes: you get what you pay for. It's possible to find a high-capacity battery for a good price, but it could be a used, restored battery. Usually made with old parts, restored cell phone batteries don't usually function as well as new ones. If the price sounds too good, chances are you're being sold a restored cell phone battery.

Most people know that a digital camera battery is an essential accessory for their digital camera. Maybe you found out that your digital camera battery consumes power so quickly that you can hardly take 50 pictures before you need to recharge or replace the battery. On the other hand, some people have high-quality digital camera batteries that seem to last forever. Of course, you just need to consider your own needs and uses for your camera before you buy a digital camera battery.

Two kinds of digital camera batteries are available today. The AA battery is very common, as is the rechargeable digital camera battery. Also known as proprietary batteries, these are usually made by the manufacturer.

Most laptops now use lithium ion (Liions) batteries. Lions should be managed differently from the Nicad or NiMH batteries used in older laptops. In particular, Lions should not be run all the way down to prevent "memory effect". First, they don't have a memory effect, and second, running them down tends to reduce their capacity. If the laptop does not need the battery it should be run to about 40% charge and stored in a cool place. Liion batteries go bad whether used or not, so only buy new Liions. Typical life is 2-3 years.

Laptop Battrties are specifically designed for each laptop brand and model. Laptop batteries are all fundamentally different from one another and cannot be substituted unless the laptop has been pre-configured from the manufacturer to accept more than one type of battery chemistry.