Advantages and disadvantages of electric vehicle batteries (lead-acid batteries, lithium batteries, Ni MH batteries)
There are many kinds of batteries for electric bicycles in the market. In addition to the largest valve regulated lead-acid batteries, nickel hydrogen batteries, nickel cadmium batteries, lithium ion batteries, zinc air batteries and so on. These batteries have their own unique advantages. Next we will recognize the characteristics and functions of each battery separately.
Lead acid battery
Among them, lead-acid battery is the largest number. Lead-acid batteries are the lowest and most commonly used. China is the world's largest producer of lead-acid batteries. It has less pollution and good recyclability. The shortcoming is that the specific volume is small. That is to say, under the same capacity, the weight and volume of the battery are large. The current lead-acid battery is basically a floating charge battery developed by the floating charge type battery, which does not adapt to fast charging and large current discharge. Although the technician has spent a lot of effort to improve the battery, it can be applied, but its life is not always ideal. Gel Battery
Colloidal batteries belong to a kind of development classification of lead-acid batteries. The simplest way is to add coagulants in sulfuric acid to turn the sulfuric acid electrolyte into a colloidal state. The electrohydraulic colloidal battery is usually referred to as a colloidal battery. Broadly speaking, the difference between colloidal battery and conventional lead-acid battery is not only that the electrobath is changed to gel. For example, non condensing solid water colloids, from the electrochemical classification structure and characteristics of the same colloidal battery. For example, in the grid, polymer materials, commonly known as ceramic gratings, can also be applied as colloidal batteries. Recently, a target coupling agent has been added to the plate formula in the laboratory, which greatly improves the utilization ratio of the active material of the plate. According to the non public data, the weight ratio of 70wh/kg can be reached. These are examples of the application of the industrial practice and the colloid electric pool to be industrialized at the present stage.
The difference between gel battery and conventional lead-acid batteries, from the original understanding of the electrolyte gel and study the electrochemical properties of electrolyte to the further development of the infrastructure and application in grid and active material in. The most important feature is that, with a smaller industrial cost, a better battery has been produced along the lead acid battery industrial road of 150 years history. Its discharge curve is straight, the turning point is high, and the power is more than 20% larger than the conventional lead acid battery, and the life is about twice as long as that of the regular lead acid battery. The characteristics of low temperature are much better.
Nickel metal hydride battery
The specific capacitance of Ni MH battery is much better than that of lead-acid battery, and the life of single cell is also better. Its charge and discharge characteristics of large current are better than that of lead-acid battery. The problem is NiMH battery management series more, after the event of a battery charger, will form a single battery separator melting problems, resulting in rapid battery failure group. So, the key technical problems of China's Ni MH battery or charger and battery management system, and this problem has not caused enough attention to the battery manufacturers and car factory. Therefore, the development of Ni MH battery has been greatly restricted. The characteristics of the large current nickel cadmium batteries nickel cadmium batteries than NiMH batteries, its anti overcharge characteristics than NiMH batteries, and China is the largest producer of the world nickel cadmium battery. Some people have raised the problem of cadmium pollution. China is still exporting large amounts of nickel cadmium battery and its application products to Europe. Europe did not begin to restrict it until 2006. According to CCTV's news, Shenzhou five uses nickel cadmium batteries. This is the advantage of its relatively high reliability, which makes the variety battery still in use and aerospace equipment. So, electric bicycles make premature exit the application of nickel cadmium batteries have some excesses? And the cost of nickel cadmium batteries and chargers are significantly lower than the cost of NiMH batteries, as long as the recycling well, the battery should be retained or varieties.
Lithium ion battery
Lithium ion battery capacity is better than the Ni MH battery, for the same capacity for lead-acid batteries, lithium ion battery, equivalent to the weight of a laptop computer, so it can be used in the elderly and infirm. Its life can also be better than a Ni MH battery. The current cell phone battery basically uses this kind of battery. The internal resistance of lithium battery is relatively large. When it is used on electric bicycles, it will feel the power of the vehicle is insufficient when the battery is about to discharge completely. The problem of lithium ion battery is mainly in the state of charge and discharge the battery will explode, mobile phone battery cells are used, through the circuit protection good to use, basically eliminate the battery explosion problem. And in the use of electric bikes, it is necessary to use serial battery protection circuit and battery protection circuit in series is far more than the complexity of a single cell, the material costs also increased significantly. At present, a good lithium battery protection circuit costs close to the price of the battery itself. The explosive damage of polymer lithium batteries is lower than that of Li ion batteries, but there is also the possibility of explosion and combustion. This is also the same as lithium-ion batteries need to solve the problem.
Zinc air battery
Zinc air battery is known for its large specific volume and low pollution. The battery is replaced by electricity, and the battery zinc plate is updated. The replacement of zinc plates can take 160 kilometers to 220 kilometers. Shanghai has launched a national set of application of zinc air battery for electric bikes in the city, the establishment of dozens of electrical outlets, pioneered the application of zinc air battery for electric bikes.