[Repost] What to do if the electric car battery has no power? Here's a trick

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[Repost] What to do if the electric car battery has no power? Here's a trick [Copy link]

This article mainly introduces the relevant information of electric vehicle batteries, and focuses on the charging problem of electric vehicle batteries. Electric vehicle batteries are the power source of electric vehicles. Most of the current electric vehicles are equipped with lead-acid batteries, which are low in cost and cost-effective. Because this battery can be charged and can be used repeatedly, it is called "lead-acid battery". In 1860, Plante of France invented a battery with lead as an electrode, which is the predecessor of lead-acid batteries. There are four types of power batteries that can be used in electric bicycles, namely valve-regulated lead-acid maintenance-free batteries, colloidal lead-acid batteries, nickel-hydrogen batteries and lithium-ion batteries. Lead-acid batteries are widely used and widely studied by various electric vehicles in various countries due to their low price, rich material sources, high specific power, mature technology and manufacturing processes, and high resource recovery rate. As a labor-saving, convenient, fast, comfortable, cheap, and zero-emission personal transportation tool, electric bicycles have been widely accepted by people and have received attention from relevant national departments. The research team of "Light Electric Vehicle Industry Development Strategy Research" participated by the Development Research Center of the State Council, the National Development and Reform Commission, the Ministry of Construction, the Ministry of Science and Technology and other ministries and commissions has put forward the "Light Electric Vehicle Industry Development Strategy Research" report. The national ownership of electric bicycles has reached more than 30 million. More than 95% of electric bicycles use valve-regulated lead-acid batteries. [1] The vast majority of commercial electric bicycles use sealed lead-acid batteries, which do not need to be frequently replenished with water during use and are maintenance-free. Its main chemical reaction is: PbO2+2H2SO4+Pb←Charge, discharge→ 2PbSO4+2H2O When the lead-acid battery is charged, the spongy lead at the positive and negative electrodes that becomes lead sulfate releases the sulfuric acid components fixed in it into the electrolyte, turning into spongy lead and lead oxide respectively, and the sulfuric acid concentration in the electrolyte continues to increase; on the contrary, when discharging, the lead oxide in the anode and the spongy lead on the cathode plate react with the sulfuric acid in the electrolyte to become lead sulfate, and the sulfuric acid concentration in the electrolyte continues to decrease. When the lead-acid battery is undercharged, the lead sulfate on the positive and negative plates cannot be completely converted into spongy lead and lead oxide. If it is undercharged for a long time, it will cause lead sulfate crystallization, sulfidation of the plates, and deterioration of the battery quality; on the contrary, if the battery is overcharged, the amount of oxygen produced by the anode is greater than the adsorption capacity of the cathode, which increases the internal pressure of the battery, causing gas overflow, electrolyte reduction, and may also cause the active material to soften or fall off, greatly shortening the battery life. The comprehensive performance has been greatly improved. In the past 10 years, the comprehensive performance of valve-regulated lead-acid batteries for electric bicycles has been greatly improved. Take the 6-DZM-10 battery as an example. In 1997, this type of battery had insufficient capacity, the discharge capacity of 2h rate (5A) did not reach 10Ah; low specific energy, the specific energy of 2h rate was less than 30Wh/kg; short life, the cycle life of 100% discharge depth was only 50~60 times (before the capacity dropped to 8Ah; the same below), and the service life was only 3~5 months. By 2003, the discharge capacity at 2h rate (5A) reached 11~13Ah; the specific energy at 2h rate reached 33~36Wh/kg; the cycle life at 100% discharge depth reached 250~300 times, and the service life could reach more than 12 months. The problems existing in valve-regulated lead-acid batteries for electric bicycles have been basically solved. The deep cycle life performance of this type of battery has made new and breakthrough progress. The main performances are: the initial discharge capacity at 2h rate (5A) reaches 14Ah; the specific energy at 2h rate reaches 38Wh/kg; the cycle life at 100% discharge depth exceeds 400 times, the total capacity released is 4500Ah, and the corresponding cumulative mileage is about 18,000km (calculated at 4km/Ah, the same below). The highest deep cycle life exceeds 600 times, the total capacity released is 6151Ah, and the corresponding cumulative mileage is about 24,600km. If the capacity is less than 7Ah as the end of life mark, the deep cycle life is 943 cycles, the total capacity released is 8710Ah, and the corresponding cumulative mileage is about 34800km. If the deep cycle life is 250 times or the total capacity released is 2250Ah, the corresponding cumulative mileage is 9000km, the battery pack can be guaranteed to be used for 1 year. [1] Pay attention to the matching with the charger. In many years of use practice, electric bicycle manufacturers and battery manufacturers have gradually realized the importance of matching between batteries and electric drive system related equipment, especially the matching with chargers. Manufacturing quality is the premise of battery quality, but only when used with a matching charger can high-quality batteries have the superior performance they should have. Otherwise, high-quality batteries cannot fully exert their potential superior performance. [1] Due to differences in formula, structure, acid concentration, etc., the appropriate charging parameters of batteries from different manufacturers are different. For example, in our research, we found that the charging parameters of batteries from different manufacturers in the constant voltage stage can differ by 1.5~2.0V (for 36V battery packs). The basic requirements for appropriate charging parameters are: ensuring that the battery can be fully charged and that the battery capacity will not decay abnormally due to undercharging; and ensuring that the battery will not lose water or produce thermal runaway due to overcharging during its entire life. [1] Lead-acid batteries for pure electric vehicles The open-type lead-acid batteries used in early pure electric vehicles adopted the research results during the "Eighth Five-Year Plan" and have achieved successful experience of being usable for 19 months (120,000 kilometers). The key is to accumulate a set of system matching work experience and careful maintenance experience such as controlling the charging method, discharge depth, and timely water replenishment. In recent years, four-wheeled micro electric vehicles (including tour buses, patrol cars, golf carts, short-distance road vehicles, etc.) have developed rapidly, and most of the vehicles use open-type lead-acid batteries. The corresponding models of batteries are favored by battery manufacturers. Electric vehicles use new products of valve-regulated sealed lead-acid batteries, whose performance is: 3h rate capacity of 55Ah; specific energy at 3h rate of 33Wh/kg and 84Wh/L; cycle life of 75% discharge depth reaches more than 400 times. It is believed that the successful experience of valve-regulated lead-acid batteries for electric bicycles can be extended to valve-regulated lead-acid batteries for pure electric vehicles, and the performance will be further improved. Lead-acid batteries for hybrid electric vehicles Hybrid electric vehicles are now basically divided into three categories: mild hybrid (i.e., the electric system is mainly used for starting and recovering braking energy, and the 42V electric system that will be promoted on all cars belongs to this type), moderate hybrid (i.e., the electric system is used for starting, recovering braking energy, and driving for medium and short distances), and heavy hybrid (i.e., the electric system is used for starting, recovering braking energy, and driving for longer distances, also known as "Plug-in"). It has been made clear in domestic and foreign literature that in mild hybrid electric vehicles, valve-controlled lead-acid batteries have advantages, mainly because of their low cost, mature technology and reliable performance; ALABC (Advanced Lead-Acid Battery Consortium) is organizing the development of valve-controlled lead-acid batteries for moderately hybrid electric vehicles, preparing to compete with MH-Ni batteries for the market of moderately hybrid electric vehicles. It has launched and conducted on-vehicle tests on wound bipolar ear batteries and TMF (metal film) batteries; in the field of heavily hybrid electric vehicles, the specific energy of lead-acid batteries is low and cannot meet the long-distance driving requirements of electric systems. Gel batteries are an improvement on ordinary lead-acid batteries with liquid electrolytes. It uses a gel electrolyte with no free liquid inside. Under the same volume, the electrolyte capacity is large, the heat capacity is large, and the heat dissipation ability is strong, which can avoid the thermal runaway phenomenon that is easy to occur in general batteries; the electrolyte concentration is low, the corrosion to the plate is weak; the concentration is uniform, and there is no acid stratification phenomenon. Nickel-metal hydride battery (Ni-MH) Nickel-metal hydride battery is a newcomer in the battery family that emerged in the 1990s and has developed rapidly. The electrode reaction of Ni-MH battery is: positive electrode: Ni (OH) 2 + OH- = NiOOH + H2O + e- negative electrode: M + H2O + e = MHab + OH-Ni (OH) 2 + M = NiOOH + MHab It is an alkaline battery like nickel-cadmium battery, but the alloy material (mh) that absorbs hydrogen replaces the negative electrode material cadmium cd in nickel-cadmium battery, and the electromotive force is still 1.32v. It has all the excellent characteristics of nickel-cadmium batteries, and its energy density is even higher than that of nickel-cadmium batteries. The main advantages are: high specific energy (long distance that can be traveled on a single charge); high specific power, stable discharge even when working at high current (good acceleration and climbing ability); good low-temperature discharge performance; long cycle life; safe and reliable, maintenance-free; no memory effect; no pollution to the environment, recyclable, and in line with the concept of sustainable development. However, Ni-MH batteries are too expensive. Lithium-ion batteries are new high-energy batteries first introduced to the market by Sony Corporation of Japan in 1990. Its advantage is high specific energy, and it is the battery with the highest specific energy at present. It has been promoted and applied in portable information products. Lithium-ion batteries are generally believed to have the following advantages: large specific energy; high specific power; small self-discharge; no memory effect; good cycle characteristics; fast discharge and high efficiency; wide operating temperature range; no environmental pollution, etc., so they are expected to become the best power sources in the 21st century. It is expected that during the period of 2006 to 2012, when lithium-ion batteries are further developed, the market share of MH/Ni batteries will shrink. The market share of lithium-ion batteries will expand. There are already electric bicycle products using lithium-ion batteries for sale. Driven by the development of new and inexpensive positive electrode materials with good safety, good cycle performance and high specific capacity, lithium-ion batteries for electric bicycles are close to practical use. Several companies can already provide relatively mature lithium-ion batteries for electric bicycles equipped with battery management systems (BMS). There are also electric bicycle manufacturers that specialize in the production of lithium-ion batteries. The author believes that lithium-ion batteries for electric bicycles will be the first power batteries to be commercialized and used in large quantities on vehicles; it will be the most practical battery after lead-acid batteries, and will also become the battery used for high-end electric bicycle products. There have been many reports on the trial and demonstration of large lithium-ion batteries in pure electric cars and electric buses, as well as in hybrid electric vehicles. According to the current development level and experience of lithium-ion batteries, it is believed that the safety of battery packs below 48V10Ah for electric bicycles is guaranteed, but there is still a lot of hard work to be done before large lithium-ion batteries can be used in commercial electric vehicles. The main reasons are: the number of batteries used in pure electric cars, electric buses, and hybrid electric vehicles is large, the system is complex, the safety is more difficult, the requirements for reliability and consistency are higher, and the price is too high. It was once reported that Shenzhen BYD would provide 200 electric cars powered by lithium-ion batteries to form a taxi fleet in 2005, but now it has been postponed to 2007. Fuel Cell Fuel cells directly convert chemical energy into electrical energy to supply electric motors to drive vehicles. Its main advantages are: high efficiency, fuel saving; zero emissions; low noise, etc., and it is particularly suitable as a vehicle power source. Hydrogen fuel cell vehicles will be ideal and will eventually replace vehicles fueled by petroleum products. Zinc-nickel battery (Zn-Ni) Zn-Ni batteries were once considered to be batteries that should be promoted for electric vehicles. From the perspective of 4 to 5 years of market screening, they are rarely used in commercial electric vehicles. This is mainly due to the high price of Zn-Ni batteries (2.5~4 yuan per VAh, 4~6 times that of lead-acid batteries); during the cycle, the initial capacity decay rate is large, which affects the actual usable life of the battery pack. In addition, the rapid development and price reduction of lithium-ion batteries have made the application of Zn-Ni batteries in electric vehicles even less competitive. Zinc-air battery Zinc-air battery is a type of metal-air battery and belongs to the category of semi-fuel cells. It has the advantages of high specific energy, abundant raw materials, low price and no pollution, and is considered to be a competitive candidate for batteries for electric vehicles. Chinese Americans once established PowerZinc in Shanghai to produce mechanically rechargeable zinc-air batteries, and a demonstration workshop has been built. The electric bicycles and electric motorcycles manufactured by the company were equipped with zinc-air batteries for mileage tests, reaching 150km and 250km respectively, and a lot of promotion and application work has been done, and 50 battery replacement points have been established in Shanghai. However, less than a year later, this promotion and trial work was stopped, and the result of market screening was that it was not accepted by users. After that, with the support of some leaders, an electric bus was built using the manufactured zinc-air battery as the power source. However, due to the poor high-power performance of the zinc-air battery, the starting and acceleration performance of the bus was significantly poor. A lot of work has been done at home and abroad on the development of zinc-air batteries for electric vehicles. In recent years, the research and development of zinc-air batteries for electric vehicles in China has re-emerged, but practice has confirmed the original superiority of zinc-air batteries, and also exposed some problems that have been reported abroad, such as the zinc electrode replacement service system and regeneration cost, the life of the oxygen electrode, and the battery electrolyte leakage, creeping or overflow. The reason and solution for the battery not storing much power in electric vehicles If the battery does not store power, it means that the battery has been vulcanized or broken or short-circuited. The vulcanized battery can be repaired with a repair instrument, and the broken or short-circuited battery needs to be manually opened and the plate replaced for repair. If the battery is depleted due to normal use, it is enough to fully charge it; but if the capacity is seriously reduced due to severe plate vulcanization or the fall of lead oxide on the anode plate, it can only be scrapped. Secondly, there are regulations on the number of times electric vehicle batteries can be charged, and the new national standard GBT 18332.1-2009 stipulates that it is 400 times. When the number of cycles is reached, the battery performance will inevitably decline, so it will lose the value of repair. Although slight sulfidation has a certain repair value, it is difficult to find in daily life, so it has no practical significance. When the battery appearance is not damaged or swollen, and there is no sign of short circuit or open circuit, you can try to repair the battery in the following ways: 1. Use positive and negative pulses to depolarize the battery and then fully discharge it. Do this three times. If there are signs of capacity recovery, you can cycle it several more times to achieve a better repair effect. 2. Add water to repair. Deionized water or purified water must be added. Do not add tap water, which will cause large self-discharge of the battery. The specific method is as follows: 1) First discharge the battery completely, because the acid density inside the battery after discharge is basically below 1.1g/mL; 2) Take out the cover, then remove the safety valve, and keep it well, do not dirty the safety valve, for later use; 3) Add water, generally 8-10g of water is added to a single cell of a 12AH battery, and about 15g of water is added to a single cell of a 20AH battery; 4) Let it stand for about an hour, and install the safety valve and the cover; 5) Charge it, and then discharge it completely after it is fully charged, and cycle it three times. Repairing electric vehicle batteries is a very professional profession, and it is necessary to master the internal structure of the battery and the battery principle. Not all batteries are worth refurbishing. Generally, if the battery life can be extended by refilling or recharging cycles, it can be repaired. Others such as no voltage and no current are not necessary. Common faults of electric vehicle batteries 1. Unbalanced repair method: find out the capacity, voltage, self-discharge, battery internal resistance, etc. and use them together. 2. Water loss repair method: Pry open the cover above the battery. Some batteries have covers bonded with ABS glue, and some batteries are connected by snaps. Some are skateboards. Be careful not to damage the cover when prying it open. At this time, you can see the rubber caps of the 6 exhaust valves. Open the rubber caps to expose the exhaust holes, and you can see the inside of the battery through the exhaust holes. The exhaust valve bases of some batteries can be unscrewed, and you can unscrew the exhaust valve base without opening the rubber exhaust valve. There are some fillers around the rubber caps of some batteries. Open the cover and shine a flashlight to see if there is any dryness inside the small hole, that is, whether the battery has lost water. The battery plates are wrapped with white fiberglass cotton, which should be moist under normal circumstances. Use a dropper to suck distilled water and inject it into the battery through the exhaust hole. Cover the exhaust hole of the battery with water with a breathable cover to prevent dust from falling into the exhaust hole. It is best to use medical double distilled water. The principle of water replenishment is to add less rather than more. If it is not enough, you can add more. If it is too much, the acid specific gravity will decrease, and the battery capacity will be insufficient. Those without experience can master it according to 5mL per hole. Special tips: Use glass, plastic and other straws as water filling tools. It is recommended to use medical disposable syringes, which are easy to use and convenient for measurement. Do not use any metal-containing instruments as water filling tools. The metal needle of the syringe should be removed and a plastic tube should be put on before use. 3. Sulfation repair method: Use the Kodi repair instrument to repair the sulfated battery. It adopts fuzzy digital control theory and measures the battery status. It continuously emits positive and negative frequency-converting particle waves while charging and discharging. It takes 10 to 20 hours to remove the lead sulfate that has become hard after crystallization in the battery. 4. Plate softening repair method: After discharging the battery to 10.5V, use a light bulb to deeply discharge for 1-5 hours. Then use an activation instrument to activate and repair. 5. Short circuit repair method: For water batteries, you can punch holes clearly to get out the short-circuited lead powder! For electric vehicle batteries, you can quickly short-circuit the positive and negative poles and burn out the short-circuited area. 6.Open circuit repair method: 100A detection battery voltage 0V is open circuit, use a single measurement method to measure the open circuit, and weld it. Use a multimeter to measure the open circuit of the battery. Conclusion This is the introduction to electric vehicle batteries. If there are any deficiencies, please correct me. Source: Internet, if infringed, please delete