What is NiCd Battery?
The nickel-cadmium battery is a popular type of rechargeable battering using the nickel hydroxide and metallic cadmium as the active chemicals. The principle advantages of NiCd over other rechargeable types is lower weight for a given quantity of stored energy, good charging efficiency, small variation in terminal voltage during discharge, low internal resistance, and non-critical charging conditions.
Sealed NiCd cells may be used individually, or assembled into battery packs containing two or more cells.
Small NiCd dry cells are used for portable electronics and toys, often using cells manufactured in the same sizes as primary cells. When NiCds are substituted for primary cells, the lower terminal voltage and smaller amperehour capacity may reduce performance over primary cells.
NiCd batteries have a niche market in the area of cordless and wireless telephones, emergency lighting, model airplanes, as well as power tools and electronic hand-held pleasure devices.
With a relatively low internal resistance, a NiCd battery can supply high surge currents. This makes them a favorable choice for remote controlled electric model aeroplanes, boats and cars, as well as cordless power tools and camera flash units |
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What is NiMH battery?
The voltage and performance of the NiMH battery is similar to standard alkaline batteries in those sizes; they can be replaced for most purposes. The ability to recharge hundreds of times can save a lot of money and resources. They are often used in digital cameras and perform well and applications that require frequent replacement of the battery, such as toys or video game controllers, also benefit from use of rechargeable batteries. With the development of low self discharge NiMH, many of occasional use applications can be replaced with NiMH rechargeable battery.
NiMH batteries are particularly advantageous for high current drain applications. Alkaline batteries, which might have approximately 3000mAh capacity under low current demand (200mA), will have less than 1000mAh capacity under 1000mA (reference). Digital cameras with LCDs and flashlights can drain over 1A, quickly depleting Alkaline batteries after few shots. NiMH can handle these current levels and maintain their full capacity. |
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What is Lithium ion Battery?
Lithium Ion Rechargeable Battery has overcome many shortcomings of conventional rechargeable batteries (NiMH, NiCd). It delivers and maintains a stable operating voltage of over 3.7V even until final discharge. Discharging three times as much voltage as NiCd or NiMH battery, its high energy density enables portable devices to be made smaller and lighter. Also, Lithium Ion Battery provides stable and consistent discharge throughout a wide temperature range with limited self-discharge to less than 10% of the original capacity per month. It has no memory effect that reduces discharge capacity and has superior recharging properties for a service life of about 500 charge/discharge cycles, i.e. much more economical than primary batteries. Lithium Ion Rechargeable Battery is suitable for cellular phones, digital still cameras, portable AV equipment, mobile games, PHSs, PDAs and wireless equipment. |
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What is Lithium Polymer Battery?
Lithium-ion polymer batteries have technologically evolved from lithium-ion batteries and have comparable energy density to lithium ion batteries. Today, demand is rising for lightweight and thin portable device. Similarly, there is a demand for a thin, lightweight battery for these applications. Lithium-ion polymer batteries are developed for this purpose.
Main Features:
More thinner and more lighter - -By using a super-light laminated aluminum film for the external packaging, lithium polymer batteries are suitable for all applications where weight, size, and durability are critical factors.
Flexible form factor - With high volume, any reasonable size can be produced economically.
Improved safety - more resistant to overcharge; less chance for electrolyte leakage
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How to prolong Li-ion battery life time?
Unlike NiCd batteries, lithium-ion batteries should be charged early and often. However, if they are not used for a longer time, they should be brought to a charge level of around 40%. Lithium-ion batteries should never be deep-cycled like NiCd batteries. Lithium-ion battery should never be depleted to below their minimum voltage, 2.4v to 3.0v.
According to one book, lithium-ion batteries should not be frozen (should not be stored below -40oC), because most lithium-ion battery electrolytes freeze at approximately -40oC (this is much colder than the lowest temperature reached by household freezers, however).
Li-ion batteries should be bought only when needed, because the aging process begins as soon as the battery is manufactured. When using a notebook computer running from fixed line power over extended periods, the battery should be removed and stored in a cool place so that it is not affected by the heat produced by the computer.
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What is the cycle life of rechargeable battery?
When a battery experiences a charge and discharge, we call a cycle or a period. In the stated charge and discharge principles and the capacity decline before a stated standard, the total cycles it can undergo called rechargeable battery cycle life.
What is battery inner impedance?
Battery impedance is the resistance when the current flow through an operating cell, in general the internal resistance is included both d.c. and a.c. resistance. For the rechargeable cell resistance is small and electrode is easy to be polarized along with producing a polarization resistance while measure d.c. resistance, the accurate value can't be measured.
What is the memory effect?
Memory effect only happens on Ni-CD batteries. As in traditional technology a Ni-CD battery's negative is agglomeration with thick Ni crystal, if Ni-CD batteries are recharged before they have been fully discharged, Ni crystal easily gathers to form agglomeration, which makes the primary discharge platform come into being. The battery stores the platform, which will be considered as the end of discharge for the next cycle even though the capacity decides that the battery can be discharged to a lower platform. The battery will store this process in its memory so during the next discharge, the battery only remembers this reduced capacity. Similarly any further incomplete discharge in each use will aggravate the effect makes lower capacity. The effect there are two methods to remove the effect: firstly deep discharge at trickle current (i.e. 0.1C to 0V), secondly several cycles at high currents (e.g. 1C).
What is "short circuit"? May I short circuit Lithium battery?
If the positive and negative terminals come into contact with each other or with a metal object, this can cause a short circuit, generating heat. If the batteries are stacked on top of each other or Mixed, the resulting short circuit can lead to heat generation, leakage, bursting and, eventually fire. Do not short circuit Lithium batteries.
May I apply heat on Lithium batteries or dispose of in fire?
If heated to 100°C or more, plastic materials in the battery such as the gasket and separator may be damaged, causing leakage. The heat generated by a short circuit inside the batteries may lead to bursting or combustion. If disposed of in fire, batteries may burn violently.
May I solder Lithium batteries directly?
If solder is applied directly to the battery, resin materials in the Lithium batteries such as the gasket and separator may be damaged due to overheating. This can cause leakage, and heat generated by a short circuit inside the battery may lead to bursting or fire. Even if no abnormality takes place immediately after soldering, the resulting leakage and other damage may harm the components attached to the battery over a long period of usage.
May I charge Primary Lithium batteries?
When a Primary Lithium battery is charged, gas is generated inside the battery and can result in swelling, heat generation, leakage bursting and fire.
May I force discharge Lithium batteries?
When batteries are force-discharged with an external power source, the voltage drops to under O V (reverse electrode), and inner gas is generated. This can lead to swelling, heating, leakage, bursting or fire.
May I disassemble, apply excessive pressure on Lithium batteries?
If a battery is disassembled by force, gas may be generated which may cause throat irritation, or the Lithium metal may generate heat, causing fire. If deformed under pressure or under impact, distortion of the seal may lead to leakage, or a short circuit inside the battery may lead to swelling, heat generation, bursting or fire.
Can I use Lithium batteries mixing with other battery types?
If different types of batteries are used together, or new batteries are used with old ones, the difference in characteristics of voltage, capacity, etc., may cause over-discharge of the battery which is exhausted first, leading to swelling, bursting or fire.
Can Lithium battery be contacted with water?
No. This may cause corrosion or the formation of combustible gas.
Can the battery be kept inside the appliance if the battery is used up or in long-term nonuse?
The battery had better be taken out from the appliance and kept in a dry place with low temperature if the appliance is in long-term nonuse. If not so, the system will still make the battery discharge a low current. It will reduce the service life of the battery.
Where Lithium batteries should be stored?
Lithium batteries should be stored in a place not exposed to direct sunlight. Make sure the area is dry and has minimal temperature variation. Storage in areas subject to high temperatures, humidity or rain may cause deterioration in battery quality and durability. To avoid short circuiting batteries during storage, be sure that the positive and negative terminals do not come in to contact with each other.
What is passivation for Li-SoCL2 battery? How to avoid the problem caused by passivation?
Passivation is a chemical term and it refers to phenomena that a kind of chemical film appears on the surface of the metal and prevents the further corrupt from happening on the surface of the metal. In lithium thionyl chloride battery, thionyl chloride is liquid. Metal lithium gets in touch with thionyl chloride completely and will slowly rust just like iron. The production of this rust is lithium chloride. The lithium chloride produced on the surface of the metal lithium in thionyl chloride is very compact and prevents the reaction of lithium and thionyl chloride. This phenomenon is passivation. The passivation of lithium thionyl chloride battery happens as soon as the battery is produced, but this reaction is not fast in speed. Just like all the chemical reaction, the speed of passivation is related to the temperature. The higher the temperature is, the faster the speed is. The longer the time is, the more serious the passivation is. Please contact EEMB sales global@eemb.com for advice about how to avoid the problem caused by passivatio.
What effect can the battery bring to the environment?
Now nearly all the battery do not contain mercury, but heavy mental is the important component for mercury battery, rechargeable nickel cadmium battery, lead acid battery. If there is improper handling, these heavy mental will have bad effect on the environment. Now, internationally there are special institutes that recall the nickel cadmium battery and lead acid battery. Our company has been devoting to replace the nickel cadmium battery with nickel mental hydride battery and lithium ion battery.
What effect can the temperature bring to the battery performance?
Among all the environmental elements, temperature has biggest effect on the battery performance. The electrochemical reaction on electrode / electrolyte interface is connected with the temperature. The electrode / electrolyte interface is considered to the heart of the battery. If the temperature gets lower, the reaction rate of the electrode also gets lower. If the battery voltage keeps invariable, the discharge current becomes lower, and also the power output will reduce. If the temperature goes up, the condition is reverse. That is, the battery's power output will increase. Temperature will also affect the speed of the transmission of the electrolyte. If the temperature goes up, the speed of transmission will be faster. If the temperature goes down, the speed of transmission will be slower. The battery performance will also be affected. But if the temperature become too higher, the chemical balance inside the battery will be broken and side reaction will be caused.
What are the possible reasons for the battery service life reduction?
Charger or charging circuit is not matching to the battery type. »»Over charge and over discharge. »»Battery type is not matching to the appliance.
What are the possible reasons for zero voltage or low voltage of the battery pack?
Single battery in the battery pack is zero voltage. »»Short circuit or open circuit of the connector or wrong connection. »»Desoldering or cold solder joint between the batteries and lead. »»Wrong connection between the batteries. There is desoldering or cold solder joint between the connection strap and battery. »»The wrong connection or failure of the electronic components inside the battery pack.
What are the possible reasons for zero voltage and low voltage of the battery?
The outside short-circuit on the battery, overcharge, or over discharge. »»The battery is continuously over charged by the very high current. »»The battery is internally short-circuited or slight short-circuited.
What are the possible reasons if the rechargeable battery or rechargeable battery pack can not be charged?
The battery is zero voltage or there is battery with zero voltage in the battery pack. »»There is wrong connection inside the battery pack. »»There is abnormity of electronic components and/or PCB inside the battery pack. »»Failure in charger. »»Outer element causes the charging efficiency to be too low, such as extremely low or high temperature.
What will happen if the batteries with different capacity are packed together?
If the batteries with different capacity or new and old batteries are used together, leakage, zero voltage and so on might happen. If the battery are rechargeable and are being charged, some batteries is overcharged and other batteries is not in full charged state. During the discharge, some batteries can not discharge fully and other batteries might over discharge. This way, the battery will be damaged. |
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