Battery

Battery

Batteries have three parts, an anode (-), a cathode (+), and the electrolyte. The cathode and anode (the positive and negative sides at either end of a traditional battery) are hooked up to an electrical circuit.

The chemical reactions in the battery causes a build up of electrons at the anode. This results in an electrical difference between the anode and the cathode. You can think of this difference as an unstable build-up of the electrons. The electrons wants to rearrange themselves to get rid of this difference. But they do this in a certain way. Electrons repel each other and try to go to a place with fewer electrons.

In a battery, the only place to go is to the cathode. But, the electrolyte keeps the electrons from going straight from the anode to the cathode within the battery. When the circuit is closed (a wire connects the cathode and the anode) the electrons will be able to get to the cathode. In the picture above, the electrons go through the wire, lighting the light bulb along the way. This is one way of describing how electrical potential causes electrons to flow through the circuit.

However, these electrochemical processes change the chemicals in anode and cathode to make them stop supplying electrons. So there is a limited amount of power available in a battery.

When you recharge a battery, you change the direction of the flow of electrons using another power source, such as solar panels. The electrochemical processes happen in reverse, and the anode and cathode are restored to their original state and can again provide full power.

Electron Flow

When the two terminals of a battery are connected by a conductor, an electric current flows. One terminal continuously sends electrons into the conductor, while the other continuously receives electrons. The current flow is caused by the voltage, or potential difference, between the terminals. Voltage is measured in units called volts. Another name for a voltage is electromotive force (EMF).

Electrons = (-) Charge / / Holes = (+) Charge

How do Batteries Work?

Battery Types

Battery labels

There is no universal standard for labeling batteries. This is a continuous source of confusion for consumers looking to replace a battery. Most manufacturers use their own labeling or designation system, which sometimes is similar to others, but not necessarily.

The International Electrotechnical Commission (IEC, http://www.iec.ch/) has proposed a standard battery designation system that provides at least some clues as to which batteries it refers to. There are two variants of this standard: 

Variant 1
The battery designation has five elements:
1. One digit for number of cells connected in series.
2. One letter to denote the electrochemical system.
3. One letter to denote shape (R=Round, P=Not Round).
4. Two or three digits as a unique physical dimension designation.
5. One or two letters as designation modifiers.
The electrochemical system is identified by the following:
L - 'Alkaline'
S - 'Silver Oxide'
C - 'Lithium/MnO2'
B - 'Lithium/CF'
For example, an 'LR44' cell uses alkaline technology (L), is round (R), and has a unique dimension identifier of 44 (11.6mm diameter, 5.4mm height). Or an 'SR44W', which uses silver oxide technology (S), is also round (R), has the same physical dimensions (44), and a modifier of 'W' to denote the 'high drain' variant, as opposed to the SR44SW which is the 'low drain' variant. 

Variant 2
The battery designation is as above, except that the physical dimension designation (element 4) is replaced by:
4a. Two-digit code denoting the maximum diameter.
4b. Two-digit code denoting the maximum height.
For example, a 'CR2032' cell uses Lithium/MnO2 technology (C), is round (R), has a maximum diameter of 20mm (20), and a maximum height of 3.2mm (32).

As indicated, not everyone sticks to these standards. The CR2032 cell is also called a DL2032 (by Duracell, no less). The SR44W has many names, including '357', 'V357', 'D357H', '228', 'J', '280-62', 'SB-B9', 'SR1154' and probably others. Competent battery suppliers (such as Battery Force at http://www.battery-force.co.uk) make finding the right battery a lot easier by maintaining cross-reference databases of all of the various codes a particular battery can have. 

Battery Data
Cell Type	Shape	Height	Diameter
AAAA	Cylindrical	42.5mm	8.3mm
AAA	Cylindrical	44.5mm	10.5mm
AA	Cylindrical	50.5mm	14.5mm
C	Cylindrical	50.0mm	26.2mm
D	Cylindrical	61.5mm	34.2mm
J	Rectangular	48.5mm	33.5 x 9.2 mm
N	Cylindrical	29.35mm	11.95mm
9-volt	Rectangular	48.5mm	26.5 x 17.5mm

AAA Batteries

The AAA battery (also called R03 or "triple-A"), is the smaller sister (or brother if you prefer your batteries to be male) of the AA battery. It is gaining in popularity quickly, and is already the second most common battery sold in the UK.

All AAA batteries share the same cylindrical shape with a height of 1.752" (44.5mm) and a diameter of 0.413" (10.5mm). Most AAA batteries use alkaline technology, with a voltage of 1.5V. The AAA battery is however also available as a rechargeable battery. The NiMH AAA rechargeable battery is rated at 1.2V, but performs as well as the alkaline version in modern high-drain applications, such as digital cameras.

The increased use of and demand for the AAA battery is the result of battery powered devices becoming smaller and more efficient, while battery technology has advanced such that a current AAA battery packs as much punch as only an AA battery could deliver a few years ago. The smaller size and reduced weight are also important considerations for the designers of the newest generation of portable CD players and other gadgets. For some devices the battery compartment and the batteries are the largest and heaviest component of the entire device! 

AA Batteries

The AA battery (sometimes affectionately called "double-A"), is the most common battery size. Every year, about 200 million are sold in the UK alone!

The AA standard actually refers to the physical dimension of the battery: cylindrical, measuring 1.988" (50mm) in height with a diameter of 0.571" (14.5mm). Amongst battery professionals, the AA battery is also called an R6.
Based on this physical standard, a large number of different AA batteries have actually been developed. They differ in performance, electrical specification, and suitability for various applications.

Zinc-Carbon AA batteries have been available for the longest amount of time. They are least expensive, and work well in low drain applications, such as portable radios or torches. They don't work well when the application requires a lot of electricity quickly, because the chemicals in the battery start deteriorating, with the result of the battery losing power. Low to moderate drain applications allow the battery chemicals to recover, and thus make for a reasonable life-span.

Alkaline AA batteries are the best general purpose AA battery available today. They provide more power then Zinc-Carbon AA batteries, and also work much better at lower temperatures. The cheapest alkaline AA battery comes close to a Zinc-Carbon battery in price, but still exceeds it in performance. A top-of-the-range alkaline AA battery, such as the Duracell Ultra M3 commands a visible premium, but outlasts not just Zinc-Carbon AA batteries, but also several other alkaline AA batteries by multiples.

More recently lithium AA batteries have emerged to power high drain devices, such as digital cameras. They clearly outperform any alkaline AA battery in such demanding electronic applications as digital photography, but this extra performance is also visible in their price.

The most economical and environmentally friendly version of the AA battery is the NiMH rechargeable AA battery. Recharging a set of NiMH AA rechargeables costs only a small percentage of the price of alkaline AA batteries, and when you've used them, you don't have to pile your used batteries into a landfill, you simply recharge them. NiMH AA rechargeables also use less dangerous materials than the previous generation of NiCd rechargeable batteries.

Rechargeable AA batteries are also typically rated at a voltage of 1.2V, rather than the 1.5V nominal voltage of the pre-charged batteries. Because of the difference in chemical process inside the battery however, the rechargeable AA battery can still outperform an alkaline AA battery in many applications.

Camcorder batteries A battery in a camcorder has a tough life. It needs to provide a high voltage for all of the clever electronics that ensure great pictures no matter where you point the camera, and also provide a strong current to drive the tape motor. This has made for pretty large camcorder batteries.  There are currently three generations of camcorder battery, all of which are still being manufactured, sold and used: • Nickel-Cadmium (NiCd) is the best established, most common, and least expensive technology.  • Nickel-Metal Hydride (NiMH) is a significant improvement over NiCd, with faster recharge times, and good performance for a much larger number recharge cycles. An NiMH battery pack will typically have a capacity 30%-50% over that of an NiCd battery pack of the same size. The NiCd memory effect, which reduces the efficiency of the battery pack with each charge/discharge cycle, has also been overcome in NiMH camcorder batteries. When the battery pack does eventually expire, NiMH is a lot friendlier to the environment, because it removes the Cadmium in NiCd battery packs from household waste.  • Lithium-Ion (Li-Ion) technology is the most recent. It outperforms the other technologies, but does so at a price. Li-Ion camcorder battery packs are also 'intelligent', in that they have on-device electronics that record usage information, and allow the battery pack to be utilized more effectively than without this information. Have you ever attempted to buy a replacement camcorder battery? You'll be surprised at the price of some original brand battery packs. It is unfortunate (for the consumer) that so many camcorders each require a special battery pack which isn't compatible with any other camera or battery pack. This of course means that the maker of the camcorder is in a good position to dominate the supply, and dictate the price. When you are looking for a camcorder, you have a wide choice, and manufacturers need to price the camcorders aggressively to compete with each other. Once you have your brand XXX camcorder, you'll also have to get their battery packs, so your ability to shop around has been dramatically reduced. Fortunately a number of third party providers have stepped in, in support of the cost-aware consumer. Uniross and Fameart are amongst the firms offering replacement camcorder battery packs for a wide variety of camcorders. Uniross is one of the leaders in rechargeable battery technology, and makes very high quality battery packs. In fact, because some of these third-party providers specialize in rechargeable batteries, their products can sometimes exceed the performance of the original battery packs, while still being less expensive.  Camera batteries Cameras tend be used very intensively over a short amount of time, and then stored for a while batteries. Lithium batteries can provide a lot of relatively high voltage power, and do so quickly. This is important when the battery needs to power the film motor, the range finder electronics, the powered zoom and a flash, nearly all at the same time. Lithium batteries also have a shelf life of 10 years of more, which means that the battery doesn't loose any of charge when it is not being used. Most of the camera batteries available today are before their next use. This has resulted in lithium batteries dominating the market for camera quite mature. The most common sizes come with labels such as CR123, CR2, 2CR5 or CRP2P. All of the big brand battery manufacturers offer these batteries, although some electronics companies (such as Panasonic), and some film companies (such as Kodak) also offer photo batteries under their brand. Because of the relative maturity of this type of battery, there are only small differences in performance between the camera batteries sold with brand names you would recognize. As such, there are great opportunities to save money by shopping around.  One more recent battery is the CR-V3. It is a 6 Volt lithium battery that will fit into a battery compartment the same size as two AA batteries. Because it doesn't waste the space between two cylindrical AA cells, it has more space for electricity producing chemicals, and will thus last longer than a pair of lithium AA batteries. Digital Camera batteries Digital Cameras place a huge burden on the batteries that provide them with power. When being used, they need a large amount of electricity very quickly. And of course it still needs to work after a month or two of being stored. Even though some alkaline batteries have very high rated capacities (up to 2500mAh), the method by which alkaline batteries convert their chemical energy into electrical energy places a limit on how much power they can produce. This gives even the best alkaline AA batteries a run for their money in power hungry digital cameras. Rechargeable batteries fare much better. The current technology used in rechargeable batteries for digital cameras uses Nickel-Metal-Hydride (NiHM) chemistry to convert the stored chemical energy into electricity. This chemical process can generate electricity far more rapidly, and will thus allow a 2100mAh NiMH battery to outperform a 2500mAh alkaline battery in a digital camera.  Current NiMH technology has a number of additional advantages over its predecessor, Nickel-Cadmium or NiCd. NiCd rechargeable batteries suffer from something called a ‘memory effect'. This reduces the amount of electricity that the battery can store in each charge/discharge cycle. Not by a great deal for each cycle, but over time you would notice that you got ever fewer pictures from your digital camera, before you had to stop to recharge.  One disadvantage that rechargeable batteries for digital cameras have not overcome is the loss of stored power while not in use. A rechargeable battery loses 1-3% of its power EVERY DAY when not in use. If you are running a professional photo studio, that won't be an issue because you're recharging every day anyway. But for a more casual user, quickly grabbing the camera  on the way to the car for a long weekend can often result in a surprise – and no pictures! Fortunately, most digital cameras are designed to also work with lithium batteries. These typically come in the same size as AA alkaline batteries, but are much better at keeping up with a digital camera's voracious appetite for power. They also have shelf lives of 10 years or more. The ideal strategy will be to rely on rechargeable batteries for most of the time, but to keep a spare set of lithium batteries handy for emergency use.  All trademarks and registered trademarks are the property of their respective owners. Hearing Aid batteries Hearing aids are designed to be small and light so that they can be worn behind, or even in the ear. Of course, they still need a suitable source of electricity to function. Hearing aid batteries have thus been optimized to be small and light. The battery technology best suited to produce light batteries is the zinc air battery. Out of all of the battery chemicals commonly in use today, it allows for the greatest amount of power to be stored for a given weight. This is a function of using air (or more precisely the oxygen in the air) as part of the chemical process to produce electricity. Because no storage is required for this chemical inside the battery, it can be made lighter.  This unique technology brings a few features of its own. Zinc are batteries are sealed when manufactured. While sealed, they have an exceptionally long shelf life. To use a zinc air battery, you have to remove the sealing tab from tiny holes on the battery to let in air. This starts the electricity producing chemical reaction. The way this chemical process proceeds makes it ideal to provide a steady current over a period of time. Zinc air batteries are not good at producing peak power quickly in a high drain application (e.g. a camera), because of the steady rate of the chemical process.  In hearing aids, this steady discharge is exactly what's required, however. Because the chemical process continues even when the battery is not used to power a device, the shelf life of a zinc air battery once un-sealed is quite limited.  Lithium-ion (Li-ion) Batteries • Very good power to weight ratio • Found in high end laptop computers and cellular phones • Now taking market share away from NiMH • Outputs 3v per cell therefore NOT directly interchangeable with normal 1.5v batteries. (sold a a unit that replaces 2, 1.5v batteries) • Made from layered sheets of aluminum foil coated with cobalt oxide, which acts as the cathode with the anode made from a thin copper sheet coated with carbon materials. • The thin film cathode and anode are separated by a sheet of plastic, rolled up together in a spiral and immersed in a liquid electrolyte medium of Lithium. • These batteries produce the same energy as NiMH batteries but are 40% smaller, half the weight, and are better for the environment because they don't contain toxic materials such as cadmium or mercury. • Currently more expensive than a comparable NiMH battery. • There are safety issues when charging - Ensure Li-ion batteries are only charged using a battery charger specifically built for the purpose. Nickel-Cadmium Batteries • Enabled the early use of portable power tools, camcorders, laptop computers and cellular phones. • Was the industry standard for portable computers until 1992. • NiCad batteries have been virtually displaced by NiMH and Li-ion. • Low energy density by weight makes it less desirable for portable computers. • NiCad batteries have a memory that prevents efficient topping up. • NiCads polute the environment if not disposed of correctly. • Low cost and high power capability make it the best technology for motor driven portable devices such as power tools. • Uses nickel hydroxide and cadmium electrodes with potassium hydroxide as the electrolyte. Nickel-Metal Hydride Batteries • Introduced in 1990 • Rapidly took market share away from NiCd batteries in the portable computing industry • Differ from NiCd only by their negative electrode which is made of a metal alloy capable of storing a large amount of electrons. • Metal hydride is produced as the charging product • Energy density is almost 50% greater than NiCad  Rechargeable batteries Rechargeable batteries do exactly what the name implies. Once you've used them, you don't dispose of the battery, you simply recharge it! Like primary batteries, rechargeable batteries have four basic components - a positive electrode (cathode), a negative electrode (anode), a separator and electrolytes. But that's where the similarities end. The chemicals inside a rechargeable battery are reversible, allowing them to be recharged again and again.  For heavy users of batteries, rechargeable batteries have always been a cheaper source of electricity. Recharging 4 batteries from mains electricity costs about 2p, whereas a new set of alkaline batteries can easily cost £4.00 or more. You don't have to be rocket scientist to realize that the slightly higher cost of buying rechargeable batteries is more than covered by savings over the life of a set of rechargeable batteries. With high performance rechargeable batteries, you can go through 1000 charge/discharge cycles before you need to replace them. That means literally hundreds of pounds saved over the use of primary batteries.  A further important consideration is how battery use affects the environment. Using rechargeable batteries reduces household waste. 15 billion ordinary batteries are thrown away every year, all of which end up in landfill sites. Rechargeable batteries can be reused which helps reduce the impact disposable batteries have on the environment.  Rechargeable batteries have been continuously enhanced to improve performance, as well as becoming more environmentally friendly. The most ecological rechargeable batteries are Ni-MH rechargeable units (Nickel-metal hydride), which are the current state-of-the-art in rechargeable battery technology.  The previous generation technology, Nickel-Cadmium, is still in use, being manufactured and sold. However, Ni-MH technology is superior in several ways:  • Ni-MH rechargeable batteries do not suffer from the Ni-Cd ‘memory effect', thus allowing a far greater number of charge/discharge cycles before the rechargeable battery's performance declines.  • Ni-MH technology is more environmentally friendly, because it avoids introducing highly toxic Cadmium from Ni-Cd cells into household waste.  Rechargeable batteries are ideal for high drain devices that use a lot of power, such as digital cameras or camcorders. But they should never be used in smoke detectors and won't work that well in other low drain devices. Here's why: Primary batteries have a much greater ability to retain their charge when not used, or when only a trickle charge is drawn from the battery. But rechargeable batteries lose some of their power every day, whether they are in a device or not.  All trademarks and registered trademarks are the property of their respective owners. Watch batteries As in many other aspects of life, for watch batteries size matters. They come in about 60 different sizes, but are all button cells and designed to pack as much energy as possible into the smallest space possible. Current watch batteries nearly all use silver oxide battery technology, because that is most efficient when squeezing the last bit of electricity into a confined space for storage. This also means that watch batteries are all rated at 1.55V, and differ primarily in their physical dimensions. Of course a large watch battery will also be able to store more electricity, and will thus be rated at a higher capacity.  Over time, the watch industry has added new features such as background lighting or audible alarms to watches. Some even feature calculators, digital diaries or other functions. This has lead to the development of additional 'high drain' versions of watch batteries to feed the extra requirement for power. In the IEC 'standard' battery designation convention, the low drain or normal version of the watch battery will end with the letter 'W', while the high drain version would end in 'SW'. A common watch battery is the SR44W (or the SR44SW for the high drain version). Because both versions have the same voltage and same physical dimensions, it is perfectly safe to use the high drain version instead of the regular version. Using the regular battery in a high drain watch will however mean that you'll have to change the battery much earlier. This interchangeability has actually led a number of watch battery manufacturers to drop the low drain version, and only produce the high drain version. When replacing your watch battery, it is useful to know that there isn't a reason for alarm when you're fitting a battery that has a different designation, just because you are upgrading to the high drain version.  Until a few years ago, several watch batteries used mercury technology. This has now been phased out for environmental reasons. Mercury is highly toxic, and there is no reasonable way to safely extract and recycle the mercury in watch batteries. For most watches, there will be a suitable replacement battery that uses silver oxide technology with the same physical dimensions. Mercury button cells did however operate with a nominal 1.35V, rather than the 1.55V of a silver oxide watch battery. Zinc-Air Batteries • Rechargeable zinc-air has emerged from its research and development phase and is now in the early stages of commercialization. • Differs from other rechargeable battery systems by extracting oxygen molecules required for electricity-producing chemical reactions directly from air. • The air electrode absorbs oxygen to generate electrical current on discharge, and expels oxygen during battery recharge. • On discharge, oxygen is brought into the cell, so there's no need to enclose a heavy metal oxidizer. • Runtime exceeds other types by far • Higher energy density, power output, and less charge time than any other battery. • Able to power a lap-top computer for over 8 hours.

All type of electrical plugs used in the world

No.	Product series	Plug Socket Type	Country
1	American product series	Type A	American Samoa, Anguilla, Antigua, Aruba, Bahamas, Bangladesh, Barbados, Bermuda, Bolivia, Brazil, Cambodia, Canada, Cayman Islands, China (without holes in blades and slightly shorter blades), Colombia, Costa Rica, Cuba, Ecuador, El Salvador, Guam, Guatemala, Guyana, Haiti, Hondurs, Jamaica, Japan, Laos, Lebanon, Liberia, Maldives, Mexico, Micronesia, Montserrat, Netherlands Antilles, Nicaragua, Niger, Okinawa, Panama, Peru, Philippines, Puerto Rico, St. Vincent, Saudi Arabia, Tahiti, Taiwan, Thailand, United States, Venezuela, Vietnam, Virgin Islands (U.S.& British), Yemen .
		Type B	All of the above noted for Type A except Bangladesh , Bolivia ,Cambodia , China , Dominican Republic , Korea , Liberia , Maldives, Peru , St. Vincent, Tahiti , Thailand , Vietnam , Yemen . Also found in Azores , Belize , Trinidad and Tobago .
		220V ONLY	Taiwan , Japan , American, Canada
		220V ONLY	Taiwan , Japan , American, Canada
2	Germany , Franceproduct series	Type E	Belgium, Burkina Faso, Burundi, Cameroon, Canary Islands, Central African Republic, Chad, Comoros, Congo, Cote d'Ivoire (Ivory Coast), Czech Republic, Djibouti, El Salvador, Equatorial Guinea, France, French Guiana, Greece, Guadeloupe, Ireland, Indonesia, Italy, Laos, Latvia, Lithuania, Madagascar, Mali, Martinique, Monaco, Morocco, Niger, Poland, St. Vincent, Senegal, Slovakia, Syria, Tahiti, Tunisia.
		Type F	Algeria, American Samoa, Aruba, Austria, Azores, Balearic Islands, Bosnia, Bulgaria, Cape Verde, Chad, Croatia, El Salvador, Finland, France, Germany, Greece, Guinea, Hungary, Iceland, Indonesia, Italy, Jordan, Korea, Laos, Luxembourg, Madeira, Monaco, Montenegro,
3	United Kingdomproduct series	Type G	Bahrain, Bangladesh, Belize, Botswana, Brunei, Cameroon, Channel Islands, China, Cyprus, Dominica, El Salvador, Gambia, Ghana, Gibraltar, Grenada, Guatemala, Guyana, Hong Kong, Iraq, Ireland, Isle of Man, Jordan, Kenya, Kuwait, Lebanon, Macau, Malawi, Malaysia, Maldives, Malta, Mauritius, Myanmar, Nigeria, Oman, Qatar, St. Kitts-Nevis, St. Lucia, St. Vincent, Saudi Arabia, Seychelles, Sierra Leone, Singapore, Tanzania, Uganda, United Arab Emirates, United Kingdom, Vietnam, Yemen, Zambia, Zimbabwe.
4	Middles East product series	Type C	, Albania, Algeria, Angola, Argentina, Austria, Azores, Balearic Islands, Bangladesh, Belgium, Bolivia, Bosnia, Brazil, Bulgaria, Burkina Faso, Burundi, Cameroon, Canary Islands, Cape Verde, Central African Republic, Channel Islands, Chile, Comoros, Congo, Croatia, Dem. Rep. of Congo (Zaire), Cote d'Ivoire (Ivory Coast), Cyrpus, Denmark, Djibouti, Egypt, El Salvador, Equatorial Guinea, Eritrea, Faeroe Islands, Finland, French Guiana, Gabon, Germany, Gibraltar, Greece, Greenland, Guadeloupe, Guinea, Guinea-Bissau, Hungary, Iceland, India, Indonesia, Iran, Iraq, Isle of Man, Israel, Italy, Kazakhstan, Korea, Kuwait, Laos, Lebanon, Lithuania, Luxembourg, Macedonia, Madagascar, Madeira, Mali, Martinique, Mauritania, Mauritius, Monaco, Montenegro, Morocco  Mozambique, Myanmar, Nepal, Netherlands, Niger, Norway, Oman, Pakistan, Paraguay, Peru, Philippines, Poland, Portugal, Romania, Russia, Rwanda, St. Vincent, Senegal, Serbia, Slovenia, Somalia, Spain, Sudan, Suriname, Sweden, Switzerland, Syria, Thailand, Togo, Tunisia, Turkey, Uruguay, Vietnam, Zambia
5	South African product series	Type D	Afghanistan, Bangladesh, Benin, Botswana, Cameroon, Chad, Dem. Rep. of Congo (Zaire), Dominica, Ecuador, El Salvador, Ethiopia, French Guiana, Ghana, Greece, Guadeloupe, Guyana, Hong Kong, India, Iraq, Jerusalem, Jordan, Kenya, Lebanon, Libya, Macao, Madagascar, Maldives, Martinique, Monaco, Myanmar (Burma), Namibia, Nepal, Niger, Nigeria, Pakistan, Qatar, St. Kitts-Nevis, Senegal, Sierra Leone, Sri Lanka, Sudan, Tanzania, United Arab Emirates, Yemen, Zambia, Zimbabwe.
		Type M	Hong Kong , Mozambique , South Africa , Swaziland .
6	Swiss product series	Type J	El Salvador , Ethiopia , Liechtenstein , Madagascar , Maldives ,Rwanda , Switzerland
7	Italy product series	Type L	Chile , Cuba , El Salvador , Ethiopia , Italy , Maldives , Syria ,Tunisia , Uruguay .
8	Egypt product series	Type H	Gaza , Israel
9	China , Australiaproduct series	Type I	American Samoa, Argentina*, Australia, China, El Salvador, Fiji, Guatemala, Kiribati, Nauru, New Zealand, Okinawa, Panama, Papua New Guinea, St. Vincent, Tajikistan, Tonga, Uruguay*
10	Denmark product series	Type K	Bangladesh , Denmark , Faeroe Islands, Greenland , Guinea ,Madagascar , Maldives , St. Vincent , Senegal , Tunisia .
Plug Type A Used in: North and Central America, Japan (see complete list of countries on above) The Type A electrical plug (or flat blade attachment plug) is an ungrounded plug with two flat parallel pins. Although the American and Japanese plugs appear identical, the neutral pin on the American plug is wider than the live pin, whereas on the Japanese plug both pins are the same size. As a result, Japanese plugs can be used in the US but often not the other way around. The pins on Type A and Type B plugs have a hole near the tip that fits into ‘bumps’ found on the contact wipers of some sockets, so that the pins are gripped more tightly allowing for better contact and also to prevent the plug from slipping out of the socket. Some sockets have spring-action blades that grip the sides of the pins, making the holes obsolete. Plug Type B Used in: North and Central America, Japan (see complete list of countries on above) The Type B electrical plug has two flat parallel pins and a round grounding (or earth) pin. The earth pin is longer than the other two so that the device is grounded before the power is connected. As with the type A plugs, the American and Japanese versions vary slightly. Type B plugs are rated at 15 amps. Plug Type C Used in: Europe, with the exception of the UK, Ireland, Cyprus and Malta (see complete list of countries on above) The Type C electrical plug (or Europlug) is a two-wire plug that has two round pins. It fits into any socket that accepts 4.0 – 4.8 mm round contacts on 19 mm centres. They are being replaced by E, F, J, K or N sockets which work perfectly with Type C plugs. Type C plugs are generally limited for use in appliances that require 2.5 amps or less. Plug Type D Used in: India, Sri Lanka, Nepal, Namibia (see complete list of countries on above) The Type D electrical plug has three large round pins in a triangular pattern. Type M plugs are often used alongside Type D plugs for larger appliances and as a result, some sockets work with both Type D and Type M plugs. Type D plugs are rated 5 amps. Plug Type E Used in: France, Belgium, Slovakia and Tunisia among others (see complete list of countries on above) The Type E electrical plug has two 4.8 mm round pins spaced 19 mm apart and a hole for the socket’s male grounding pin. The Type E socket is different to the Type F socket which is standard in other continental European countries, such as Germany. The CEE 7/7 plug was developed to work with sockets E and F and has grounding clips on both sides (to work with Type F sockets) and a female contact (to accept the grounding pin of the type E socket). Type E plugs are rated 16 amps. Plug Type F Used in: Germany, Austria, the Netherlands and Spain among others (see complete list of countries on above) The Type F electrical plug (also known as a Schuko plug) has two 4.8 mm round pins spaced 19 mm apart. It is similar to the Type E plug but has two earth clips on the side rather than a female  earth contact. The CEE 7/7 plug was developed to work with sockets E and F and has grounding clips on both sides (to work with Type F sockets) and a female contact (to accept the grounding pin of the type E socket). Type F plugs are rated 16 amps. Plug Type G Used in: UK, Ireland, Cyprus, Malta, Malaysia, Singapore, Hong Kong (see complete list of countries on above) The Type G electrical plug has three rectangular blades in a triangular pattern and has an incorporated fuse (usually a 3 amps fuse for smaller appliances such as a computer and a 13 amps one for heavy duty appliances such as heaters). British sockets have shutters on the live and neutral contacts so that foreign objects can’t be introduced into them. Plug Type H Used in: Israel The Type H plug is unique to Israel and has two flat pins in a V-shape as well as a grounding pin. It is however currently being phased out in favour of a round-pinned version. The holes in Type H sockets are wide in the middle so as to accommodate the round-pinned version of the Type H plug as well as Type C plugs. Type H plugs are rated 16 amps. Plug Type I Used in: Australia, New Zealand, Papua New Guinea, Argentina (see complete list of countries on above) The Type I plug has two flat pins in a V-shape as well as a grounding pin. A version of the plug, which only has the two flat pins, exists as well. The Australian plug also works with sockets in China. Australia’s standard plug/socket system is rated 10 amps but a plug/socket configuration rated 15 amps also exists, although the ground pin is wider. A standard 10 amp plug will fit into a 15 amp socket but not the other way around. Plug Type J Used in: Switzerland and Lichtenstein (see complete list of countries on above) The Type J plug has two round pins as well as a grounding pin. Although the Type J plug looks a lot like the Brazilian Type N plug it is incompatible with the Type N socket as the earth pin is further away from the centre line than on Type N. However, Type C plugs are perfectly compatible with Type J sockets. Type J plugs are rated 10 amps. Plug Type K Used in: Denmark and Greenland (see complete list of countries on above) The Type K plug has two round pins as well as a grounding pin. It is similar to Type F, the difference being that Type F has grounding clips instead of a grounding pin. Type C plugs are perfectly compatible with Type F sockets. Type E plugs and sockets are also used in Denmark. Plug Type L Used in: Italy (see complete list of countries on above) There are two variations of the Type L plug, one rated at 10 amps, and one at 16 amps. The 10 amp version has two round pins that are 4 mm think and spaced 5.5 mm apart, with a grounding pin in the middle. The 16 amp version has two round pins that are 5 mm thick, spaced 8mm apart, as well as a grounding pin. Italy has a kind of “universal” socket that comprises a “schuko” socket for C, E, F and L plugs and a “bipasso” socket for L and C plugs. Plug Type M Used in: South Africa, Swaziland, Lesotho (see complete list of countries on above) The Type M plug has three round pins in a triangular pattern and looks similar to the Indian Type D plug, but its pins are much larger. Type M plugs are sometimes used for bigger appliances in countries that make use of Type D plugs, as well as in Israel (Type H). Therefore, sockets in these countries sometimes work with Type M plugs. Plug Type N Used in: Brazil (see complete list of countries on above) There are two variations of the Type N plug, one rated at 10 amps, and one at 20 amps. The 10 amp version has two round pins that are 4 mm thick, and a grounding pin. The 20 amp version, used for heavier appliances, has two round pins 4.8 mm in diameter, and a grounding pin. The Type N socket was designed to work with Type C plugs as well. Brazil is one of the few countries that uses two types of voltage. While most states use 127 V, some of them use 220 V. It is therefore important to find out the local voltage before plugging in your appliance (note: wrong voltage can destroy your appliance). Many appliances sold in Brazil are dual voltage.