For many years, only nickel-cadmium batteries qualified as portable devices, whether for wireless communications, mobile computing, or periods in between. In the early 1990s, nickel-metal oxides and lithium ions appeared. There is fierce competition for customers’ approval. Currently, lithium-ion batteries are the fastest growing and most promising battery chemistry among all battery types.
The lithium-ion battery
Lithium ion batteries carried out pioneering work in lithium batteries in 1912 under G.N. Lewis. Still, it was not until the early 1970s that non-rechargeable models of lithium batteries first entered the market. As the lightest of the metals, lithium is, at the same time, the most electrochemical potential and provides the most significant weight energy density.
The rechargeable lithium-ion battery failed due to safety issues. At the same time, due to the instability of the lithium metal element itself, especially in the charging process, the research turned to the use of lithium ion non-metallic lithium batteries. Although lithium metal has slightly more energy than lithium ions, it is safe as precautions are taken during charging and discharging. In 1991, SONY commercialized the first lithium-ion battery. Other manufacturers have followed suit.
Lithium ion has one advantage that most other chemicals don’t: it’s a low-maintenance battery. Lithium-ion batteries have no memory and do not require periodic cycles to extend the battery’s life. In addition, lithium-ion batteries have less than half the self-discharge capacity of nickel-cadmium batteries, making them ideal for modern fuel metering applications. Lithium-ion batteries cause almost no harm during processing.
While lithium ion has overall advantages, it also has their disadvantages. For example, lithium ion is very fragile. Therefore, a protection circuit is needed to protect lithium ions to maintain a safe operating environment. The protection circuit is built into each package to cover the course by limiting the peak voltage of each battery during charging while also preventing the battery voltage from dropping to produce too low a discharge. In addition, lithium-ion batteries will continuously monitor the battery temperature without avoiding extreme temperatures. Most battery packs’ maximum charge and discharge current are limited to 1C to 2C. A lithium ion battery will eliminate overcharging lithium metal coating with the above preventive measures.
Aging is a common problem with most lithium-ion batteries, and many manufacturers have chosen to keep quiet about it because there is nothing they can do about it. After a year of use, the battery’s capacity drops significantly, whether or not it has been used. Batteries also often fail after the second or third year. At the same time, we also need to be aware that other chemicals have age-related degradation problems. This is especially true of nickel metal hydrides when exposed to high temperatures for long periods. At the same time, we all know that lithium-ion battery packs in many applications last up to five years.
Today, manufacturers constantly improve lithium-ion batteries, introducing new and enhanced chemical combinations about every six months. With such rapid development, it is difficult to assess the aging of new batteries. Lithium ions (and other chemicals) can slow the aging process when stored in a cool place. The appropriate storage temperature recommended by the manufacturer is 15 degrees Celsius. In addition, the battery should partially charge the battery during storage. Manufacturers suggest setting users 40 percent.
Regarding the power-to-cost ratio, the most economical lithium-ion battery is the cylindrical 18650 (18nm by 65.2nm). This unit is needed for mobile computing and other applications that do not require ultra-thin geometry. But if you need an ultra-thin battery pack, prismatic lithium-ion batteries are the way to go because they cost more to store energy.
Advantages
Higher potential – the ability to have the high energy density
At the new time, there is no need for a long boot. A regular charge is enough.
The free discharge is relatively low – less than half that of nickel-based batteries.
No memory, no high maintenance, no periodic discharge.
A battery can provide applications such as power tools with higher current from dedicated batteries.
Limitations
Keep current and voltage within safe limits by protecting the circuit.
Extremely susceptible to aging, even when not in use – store it in a cool place and charge it 40 percent to reduce the effects of aging.
Restrictions on shipments: Controls on shipments in large quantities but do not apply to batteries carried by individuals.
High manufacturing cost, 40% higher than the cost of nickel chrome.
The lithium polymer battery
This lithium polymer is different from conventional battery systems because of the type of electrolyte it uses. Dating back to the 1970s, the original design used a dry-solid polymer electrolyte, which acts much like a thin film of plastic and allows for exchanging ions (with dotted origins or groups of atoms) without conducting electricity. Traditional porous membranes are replaced by polymer electrolytes, which soak the porous membranes.
The design of dry polymers has been simplified in terms of manufacturing, robustness, safety, and thin geometry. The battery is only 1 millimeter (0.039 inches) thick, so device designers can only imagine shapes and shapes and sizes.
Unfortunately, the dry lithium polymer is very poor at conducting electricity. Because of their high internal resistance, dry lithium polymers cannot deliver the current needed by hard disk drives in modern communications and mobile computing devices. Heating the battery to 60 ° C (140°F) or higher increases conductivity, but this requirement does not apply to portable applications.
As a compromise, a gel electrolyte was added. Commercial batteries use separation/electrolyte membranes made from traditional porous polyethylene filled with polymers or polypropylene separation membranes to replenish liquid electrolytes and form gels. As a result, commercially used lithium-ion polymers are chemically and materially similar to their liquid electrolyte counterparts.
Lithium-ion polymers haven’t caught on quickly, but some analysts expect them to. Compared to other systems, lithium ion polymers’ advantages and manufacturing costs have not been fully demonstrated. The capacity of lithium-ion polymer batteries is slightly smaller than that of standard lithium-ion batteries, and the degree of lithium-ion polymer batteries has not improved. Lithium-ion polymers have found their niche in fragile geometry, such as credit card batteries and similar applications.
Lithium polymer battery advantages
Extremely understated — as workable as a credit card battery.
Flexible form factor – so manufacturers are not constrained by standard cell formats, and the battery can economically produce any reasonable size on a large scale.
The lightweight gel electrolyte simplifies packaging by eliminating the metal casing.
Because it is more resistant to overcharge, the safety is improved, and the chance of electrolyte leakage is slight.
Limitations
Compared with lithium ion, it has a lower energy density and fewer cycles.
Very expensive to manufacture.
Because the high-volume consumer market produces most batteries, there is no standard size.
Compared to the cost of lithium-ion batteries, the energy ratio is higher.
Restrictions on lithium content for air travel
We first divide lithium batteries into two types: lithium metal and lithium ion batteries. Most lithium-metal batteries that batteries can use in film cameras are not rechargeable. Lithium-ion batteries can charge mobile phones, video cameras, and laptops. You can carry both types of batteries (including spare packs). Still, the lithium content should not exceed 2 grams of lithium metal or lithium alloy batteries or 8 grams of lithium ion batteries.
Lithium ion batteries more significant than 8 grams and less than or equal to 25 grams can be carried in carry-on luggage when separate protection prevents a short circuit. No one can take a maximum of 2 quick spare batteries.
How do we learn about the gold content of lithium-ion batteries? In theory, lithium metal is not present in typical lithium-ion batteries. However, the battery must take lithium content into account. For lithium-ion batteries, this is 0.3 times the rated capacity (measured in ampere-hours).
For example, 0.6 grams of lithium is present in a 2Ah 18650 lithium-ion battery. A typical 60Wh laptop battery with eight batteries (four in series and two in parallel) adds up to 4.8g. To stay within the LIMIT set by the UN, no more than 8g, so the maximum battery you can carry is 96Wh. The package can include 2.2A cells and 12 arranged cells (4s3P). If you want to use a 2.4Ah battery, the battery pack should be limited to 9 cells (3S3P).
Restrictions on shipment of lithium-ion batteries
The personnel responsible for any lithium ion batteries shipped in bulk comply with shipping regulations, which apply to domestic land, sea, and air transport and international land, sea, and air transport.
When the lithium ion battery contains more than 1.5 grams of lithium or more than 8 grams, it must transport under “Class 9 miscellaneous hazardous substance” conditions. Lithium is determined by battery capacity and the number of cells in a battery pack.
Except for packages containing less than 8 grams of lithium. However, shipments containing more than 24 lithium batteries or 12 lithium ion battery packs require special labeling and shipping documentation. Every package must indicate that it has lithium batteries.
Regardless of the lithium content (UN Manual of Tests and Criteria, Part III, subsection 38.3), all lithium ion batteries must be tested following the specifications described, SENTENCE UN3090. Such measures can effectively prevent the transport of defective batteries.
The battery and battery components should be packed separately in a solid box to prevent short circuits.