With the development of science and technology and electrochemical materials and process technology, people continue to research, develop new battery materials and new batteries. Following the nickel-cadmium, nickel metal hydride rechargeable battery, developed in 1991 a rechargeable lithium-ion battery, better performance in 1995 introduced the lithium polymer battery, 2002, the new lithium iron phosphate has come out.
Currently on the market lithium-ion battery cathode material of lithium cobalt oxide is mainly (LiCoO2), plus a few uses lithium manganese oxide (LiMn2O4) and lithium nickel oxide (LiNiO2) as a cathode material. Is a new type of lithium iron phosphate lithium iron phosphate (LiFePO4) as cathode, graphite for the negative electrode of lithium-ion battery. It works exactly the same with the lithium-ion batteries, lithium-ion battery in the new family member.
The full name of lithium iron phosphate, lithium iron phosphate should be lithium-ion battery, the name is too long, referred to as lithium iron phosphate battery. Since the battery is ideal for battery powered, so often call it lithium iron phosphate battery, there are more simply referred to as lithium iron battery (LiFe Power Battery). This is an abbreviation of LiFePO4 batteries.
In the above-described cathode material for lithium-ion battery, its metal elements cobalt (Co) the most expensive, and the amount of the world, Yun-hide, soon after, followed by nickel (Ni), manganese (Mn) are cheaper, and iron (Fe) the cheapest. Cathode material prices and the market price of the same metal. Therefore, LiFePO4 battery should be the most expensive. In addition it has a flat discharge performance, especially, can use a large discharge rate of discharge (5 ~ 10C), special security (will not overcharge, over discharge, short circuit occurs even when the fire or explosion), long cycle life, environmental no pollution, high-current output power as a battery, its performance is the best.
Currently there are a number of factories to produce LiFePO4 cathode material, some plants have a variety of small batch production capacity of LiFePO4 battery (mAh capacity from several hundred to several hundred Ah). As production time is not long, not yield, or start-up phase, so far in price than the same capacity lithium-ion battery is also expensive, and also in short supply, often out of stock. This phenomenon will be improved 1 to 2 years. Then the price of LiFePO4 batteries is more complete, and further progress in the quality, prices cheaper, more widely applied.
According to the latest news: Recently, the Iowa State University and Ames lab found that the use of polymer solar cells bottom lines.
Studies have shown that this material layer has its own uniqueness. Even less than millionths of a meter in the undulating surface was also able to maintain uniform thickness, a thin, uniform layer of material and absorbance was making was bottom lines. Polymer photovoltaic cells can be obtained through these folds absorb more light – was included in the fold between the reflected light.
The cell surface was too light absorption was also able to maintain good electrical conductivity. The effective use of technology, light trapping device mechanism, the efficiency of photovoltaic cells can have increased by 20%.
Test also showed that compared with the flat photovoltaic cells, the edge of near-infrared spectrum of light increased nearly 100%. Folds have a much larger layer has a higher energy conversion efficiency obtained was space, which is captured by the light, especially longer wavelength photon capture efficiency was raised to cause too.
It is understood that the material can be widely used in conventional silicon-based photovoltaic cells, batteries and can improve the conversion rate of photovoltaic cells is a new revolution.
Into lithium-ion batteries and lithium batteries lithium polymer battery. Lithium-ion batteryelectrolyte is flowing, the polymer electrolyte is a solid-state lithium batteries and, therefore,lithium polymer lithium-ion battery is more than the unstable encounter external beat, or usenon-standard charger, may cause battery to explode. Many mobile phones, laptops, digital cameras and other portable electronic products used in batteries are lithium batteries. Buypoor quality lithium batteries, as his side put in a ”time bomb.” Therefore, when consumersbuy lithium batteries must note the following:
1. Capacity is clearly marked. No clearly marked capacity (such as 2200mAh or 4400mAh)lithium battery, it is likely that use of poor quality battery cell or battery cell recycling of waste batteries re-assembled. Market filled with many low-cost lithium batteries, is the use of recycled cells or disassemble the battery cell to do, the price is cheap, but life is short, inconsistent quality, the use of mistake may damage the phone, or even an explosion.
2. Standby time is guaranteed. Standby time after the battery into the phone to the nextcharge of continuous use. Lithium batteries on the market generally can not be guaranteedto the customer standby time, which is unstable because of the quality of the relationship between the battery, many batteries as is the use of cheap poor quality of the battery cell,so standby time is very short.
3. It with safety protection circuit. The nature of the lithium battery protection board must beapplied to prevent the lithium battery overcharge, over discharge and short circuithappening, without the lithium battery protection board will be deformation, leakage,explosion. In the fierce price competition, the battery packaging plant protection circuit fora lower price, or simply omit the device, making the market filled with potentially explosivelithium battery. Consumers can not tell from the appearance of the protection circuit boardout there, so the best choice to buy from reputable merchants.