1, lithium-ion batteries generations of Change
The first generation of lithium-ion VGP-BPS2A VGP-BPS9A batteries: anode: lithium metal, the tensions of work to 3.7V. Since lithium directly to a very bright as a negative, too many security risks have been eliminated.
The second generation: low-power lithium-ion batteries liquid. Anode material allotrope C, operating voltage was reduced to 3.6 V. It avoids directly to the lithium metal as the potential security problems of anode are generally used for laptops, cameras and so on.
Third-generation polymer lithium-ion battery. The electrolyte does not flow from freezing solid material can be made into any shape, size. Great capacity but not high current discharge for mobile phones, MP3 and other computer products market power by a smaller favor.
The fourth-generation high-power lithium-ion battery. High capacity, clean and high current (power) discharge. Electric bicycles and electric vehicles as a high power battery.
Secondly, the advantages of lithium batteries
1. Lithium is the lightest metal in nature, specific gravity and water is only 1 / 2, so the quality lithium-ion batteries that high. Usually cadmium – nickel-2 to 3 times, hydrogen – The nickel was ~ 2-foldIBM ThinkPad R52 battery IBM ThinkPad T40 battery
2. Lithium atom / ion radius smaller volume ratio of hydrogen – rechargeable nickel to 30% smaller than the size of its energy is also high. Usually cadmium – nickel-two times more hydrogen – rechargeable nickel 1.5 times.
3. Thirdly, lithium is the least electronegativity, the standard redox potential of – 3.045 V (hydrogen electrode reference is concerned). Therefore, both find as suitable cathode material, you can get a high electromotive force, which currently operates 3 to 4 volts, is cadmium – nickel, hydrogen – nickel 3 times.
4. And most sources of chemical energy with a different aqueous solution as electrolyte, lithium-ion batteries use organic solvents as an electrolyte. Therefore, the lithium-ion batteries often used with a wide range of temperature, usually 20 ℃ ~ 60 ℃, particularly adapted for use at low temperature. The solution near the battery to 0 ℃, which is a result of electrolyte freezing completely discarded.
5. Lithium-ion batteries containing heavy metal elements (such as lead acid batteries in Pb) and toxic elements (such as cadmium – nickel batteries in Ge) do not cause environmental pollution, they been known as the green battery.
6. Lithium battery voltage discharge ion plate, no memory effect, little self-discharge cycle life long, but it is also an important advantage. Dell Inspiron 1300 battery Dell Inspiron 1420 battery
3, the security risks of lithium batteries come from?
(1) Lithium-essential ion battery: Li animated metals in the non-normal circumstances (eg, overload), Li + may be negative to be electronic, not precipitation lithium metal, and assembled in a dendrite lithium perforated diaphragm, connectivity is negative, causing internal short-circuit the battery. In addition, in the case of air or water, the precipitation of lithium metal but also extremely insecure factors.
(2) lithium-ion battery electrolytes: conductivity is low flammability, oxidation and reduction of solution. Battery voltage lithium 3 ~ 4 V, the traditional theory of the tension of the electrolyte solution 1.23 V, the lithium battery of high-voltage electrolysis of water has long been recognized. Thus, lithium batteries can only be due to high compression, high-boiling point organic electrolyte. Organic solution has the disadvantage of generally conductivity (eg high resistance) in short-circuit and overload of work, the high current rapidly cause the battery’s internal heat, which triggers the combustion of electrolyte in overload, where too discharge electrolysis solution is oxidized or restoration, the production of a large number of gas, so that sealed lithium-ion battery is even a risk of explosion! In addition, the internal temperature of the battery and the battery are a couple of reaction intensified in the vicious circle of positive feedback, leading to fire or explosion of battery of short duration. hp Pavilion DV1000 battery hp Pavilion dv4000 battery
4, power-based lithium-safety requirements on ion batteries as lithium-ion battery means more
(1), large capacity requirements of safety higher: the power type lithium-ion batteries and the combination of the battery capacity is 1.3Ah, 1.5AH, 3Ah, 3.5AH, 7Ah, 10Ah, 14Ah, 20Ah or higher is lithium-ion batteries in general several times. Large capacity for materials micro-performance lithium-ion battery anode are being de-embedded / embedded in the number of lithium-ion batteries, which will increase its security implications.
(2) Discharge high power safety requirements are higher: low-power lithium ion batteries, they are less active in the power of the computer products market, and power lithium-ion batteries used in electric, powered vehicles and military player. The power to fulfill the latter is much larger than the first, namely, the internal battery to withstand the current is much larger than the former, but as mentioned earlier, organic electrolytes by strong currents (typically up ’safety of several or even dozens of security), is also a lithium-ion a risk factor for the battery.
(3) the use of harsh conditions on the security requirements are higher: the battery type lithium-ion power commonly used in difficult conditions, such as electric vehicles as a power source, they work full air, to withstand changes in temperature in its impact, while benefiting from bumps and emergency stop, accelerate test extrinsic motivation. PA3399U-1BRS PA3399U-2BAS
Therefore, lithium power type, the security issues that ion battery using lithium-ion battery is more prominent, higher requirements. How to solve this problem, also from the material, structure and circuit protection to begin. Finally, and scientific testing and certification authority, so it can provide efficient and safe power type lithium-ion delivered to the customer’s hands.
5, the security issues resolved?
One, materials, start with a selection of over safety of lithium manganese oxide, lithium iron phosphate cathode material B as a reasonable choice of anode material for C temperature characteristics over the selection of membrane materials and better temperature characteristics of D, a higher pressure, electrical conductivity and better electrolyte formula E a reasonable proportion of positive and negative materials
2 Circuit A reliable external peripheral circuits are designed to ensure reliability, failure analysis prepared to reduce the working batteries in extreme conditions, the probability, so that the batteries operate in a reasonable condition B processes and materials to ensure the reliability of the circuitA1022 A1078
3, the strict inspection and monitoring.