Rechargeable Lithium Ion Batteries – Locate a Electric Power Supply to Fit All of Your Battery Powered Equipment.
For many years, nickel-cadmium ended up being the only real suitable battery for ODM electronic devices Lithium-Polymer batteries from wireless communications to mobile computing. Nickel-metal-hydride and lithium-ion emerged In early 1990s, fighting nose-to-nose to acquire customer’s acceptance. Today, lithium-ion is definitely the fastest growing and most promising battery chemistry.
Pioneer deal with the lithium battery began in 1912 under G.N. Lewis nevertheless it had not been up until the early 1970s when the first non-rechargeable lithium batteries became commercially available. lithium may be the lightest of metals, offers the greatest electrochemical potential and offers the greatest energy density for weight.
Efforts to develop rechargeable lithium batteries failed because of safety problems. As a result of inherent instability of lithium metal, especially during charging, research shifted to a non-metallic lithium battery using lithium ions. Although slightly lower in energy density than lithium metal, lithium-ion remains safe and secure, provided certain precautions are met when charging and discharging. In 1991, the Sony Corporation commercialized the 1st lithium-ion battery. Other manufacturers followed suit.
The electricity density of lithium-ion is typically twice that relating to the typical nickel-cadmium. There exists potential for higher energy densities. The stress characteristics are reasonably good and behave similarly to nickel-cadmium regarding discharge. The high cell voltage of three.6 volts allows battery pack designs with just one cell. Most of today’s mobile phone devices run on one cell. A nickel-based pack would require three 1.2-volt cells connected in series.
Lithium-ion is a low maintenance battery, an edge that many other chemistries cannot claim. There is no memory and no scheduled cycling must prolong the battery’s life. In addition, the self-discharge is less than half when compared with nickel-cadmium, making lithium-ion well designed for modern fuel gauge applications. lithium-ion cells cause little harm when disposed.
Despite its overall advantages, lithium-ion has its drawbacks. It is fragile and needs a protection circuit to preserve safe operation. Included in each pack, the protection circuit limits the peak voltage for each cell during charge and prevents the cell voltage from dropping too low on discharge. In addition, the cell temperature is monitored to prevent temperature extremes. The highest charge and discharge current on many packs are is restricted to between 1C and 2C. By using these precautions in position, the potential of metallic lithium plating occurring on account of overcharge is virtually eliminated.
Aging is a concern with a lot of Innovative battery technology and a lot of manufacturers remain silent about this issue. Some capacity deterioration is noticeable after 1 year, whether the battery is use or perhaps not. The battery frequently fails after a couple of years. It ought to be noted that other chemistries also have age-related degenerative effects. This is also true for nickel-metal-hydride if in contact with high ambient temperatures. Concurrently, lithium-ion packs are acknowledged to have served for 5yrs in certain applications.
Manufacturers are constantly improving lithium-ion. New and enhanced chemical combinations are introduced every six months or so. By using these rapid progress, it is sometimes complicated to evaluate how well the revised battery will age.
Storage inside a cool place slows getting older of lithium-ion (and also other chemistries). Manufacturers recommend storage temperatures of 15°C (59°F). In addition, the battery should be partially charged during storage. The company recommends a 40% charge.
Probably the most economical lithium-ion battery regarding cost-to-energy ratio may be the cylindrical 18650 (dimension is 18mm x 65.2mm). This cell is used for mobile computing and also other applications which do not demand ultra-thin geometry. If a slim pack is required, the prismatic lithium-ion cell is the greatest choice. These cells come in a higher cost when it comes to stored energy.
High energy density – potential for yet higher capacities.
Does not need prolonged priming when new. One regular charge is all that’s needed.
Relatively low self-discharge – self-discharge is not even half that from nickel-based batteries.
Low Maintenance – no periodic discharge is required; there is not any memory.
Specialty cells can provide high current to applications including power tools.
Requires protection circuit to keep voltage and current within safe limits.
Subject to aging, even if not in use – storage in a cool place at 40% charge reduces the aging effect.
Transportation restrictions – shipment of larger quantities could be susceptible to regulatory control. This restriction does not affect personal carry-on batteries.
Expensive to manufacture – about 40 % higher in cost than nickel-cadmium.
Not fully mature – metals and chemicals are changing on the continuing basis.
The lithium-polymer differentiates itself from conventional battery systems in the particular electrolyte used. The original design, going back to the 1970s, works with a dry solid polymer electrolyte. This electrolyte resembles a plastic-like film that is not going to conduct electricity but allows ions exchange (electrically charged atoms or teams of atoms). The polymer electrolyte replaces the regular porous separator, which is soaked with electrolyte.
The dry polymer design offers simplifications with regards to fabrication, ruggedness, safety and thin-profile geometry. Having a cell thickness measuring well under one millimeter (.039 inches), equipment designers stay to their own imagination in terms of form, size and shape.
Unfortunately, the dry lithium-polymer is experiencing poor conductivity. The inner resistance is way too high and cannot give you the current bursts found it necessary to power modern communication devices and spin within the hard drives of mobile computing equipment. Heating the cell to 60°C (140°F) and better raises the conductivity, a requirement which is unsuitable for portable applications.
To compromise, some gelled electrolyte is added. The commercial cells utilize a separator/ electrolyte membrane prepared from the same traditional porous polyethylene or polypropylene separator filled with a polymer, which gels upon filling together with the liquid electrolyte. Thus the commercial lithium-ion polymer cells are very similar in chemistry and materials to their liquid electrolyte counter parts.
Lithium-ion-polymer has not yet caught on as quickly as some analysts had expected. Its superiority for some other systems and low manufacturing costs has not been realized. No improvements in capacity gains are achieved – in reality, the ability is slightly less than that of the regular lithium-ion battery. Lithium-ion-polymer finds its market niche in wafer-thin geometries, such as batteries for bank cards along with other such applications.
Very low profile – batteries resembling the profile of credit cards are feasible.
Flexible form factor – manufacturers are not bound by standard cell formats. With good volume, any reasonable size can be produced economically.
Lightweight – gelled electrolytes enable simplified packaging by reducing the metal shell.
Improved safety – more proof against overcharge; less chance for electrolyte leakage.
Lower energy density and decreased cycle count in comparison with lithium-ion.
Expensive to manufacture.
No standard sizes. Most cells are made for high volume consumer markets.
Higher cost-to-energy ratio than lithium-ion
Restrictions on lithium content for air travel
Air travelers ask the question, “Just how much lithium within a battery am I able to bring aboard?” We differentiate between two battery types: Lithium metal and lithium-ion.
Most lithium metal batteries are non-rechargeable and they are found in film cameras. Lithium-ion packs are rechargeable and power laptops, cellular phones and camcorders. Both battery types, including spare packs, are allowed as carry-on but cannot exceed the subsequent lithium content:
– 2 grams for lithium metal or lithium alloy batteries
– 8 grams for lithium-ion batteries
Lithium-ion batteries exceeding 8 grams but not more than 25 grams may be carried in carry-on baggage if individually protected in order to avoid short circuits and they are confined to two spare batteries per person.
Just how do i know the lithium content of a lithium-ion battery? From the theoretical perspective, there is no metallic lithium inside a typical lithium-ion battery. There is, however, equivalent lithium content that must definitely be considered. For the lithium-ion cell, this really is calculated at .3 times the rated capacity (in ampere-hours).
Example: A 2Ah 18650 Li-ion cell has .6 grams of lithium content. On a typical 60 Wh laptop battery with 8 cells (4 in series and 2 in parallel), this adds up to 4.8g. To stay under the 8-gram UN limit, the Outdoor Power Equipment battery packs you can bring is 96 Wh. This pack could include 2.2Ah cells in the 12 cells arrangement (4s3p). When the 2.4Ah cell were utilized instead, the pack would need to be limited to 9 cells (3s3p).
Restrictions on shipment of lithium-ion batteries
Anyone shipping lithium-ion batteries in mass is responsible in order to meet transportation regulations. This is applicable to domestic and international shipments by land, sea and air.
Lithium-ion cells whose equivalent lithium content exceeds 1.5 grams or 8 grams per battery pack has to be shipped as “Class 9 miscellaneous hazardous material.” Cell capacity 18dexmpky the volume of cells within a pack determine the lithium content.
Exception is given to packs that have below 8 grams of lithium content. If, however, a shipment contains a lot more than 24 lithium cells or 12 lithium-ion battery packs, special markings and shipping documents will likely be required. Each package must be marked which it contains lithium batteries.
All lithium-ion batteries must be tested in accordance with specifications detailed in UN 3090 regardless of lithium content (UN manual of Tests and Criteria, Part III, subsection 38.3). This precaution safeguards against the shipment of flawed batteries.
Cells & batteries should be separated to avoid short-circuiting and packaged in strong boxes.