- according to "weekly quality report" Report
In April, a car park at a university campus in Fujian burst into flames early in the morning, with hundreds of bicycles and electric bicycles burned and some burned to a skeleton. In front of the fire shed a plug for electric vehicle charging, there are many burned electric vehicles connect the charger, the fire department preliminary determination for the electric vehicle charging fire. Fortunately, the fire did not cause casualties.
According to data from the electric bicycle industry, the probability of an electric bicycle fire every year is 2/100000. At present, China's electric bicycle society has more than 200 million, the fire department to fire probability 1/100000 for conservative calculation, each year by the electric bicycle fire caused by about 2000. It is worth noting that the survey data provided by the fire department show that 75% of the electric bicycle fires occurred during charging.
As an indispensable accessory of the electric bicycle, the charger's quality decides whether the electric bicycle is safe when charging. Because the domestic common battery charger to enter the threshold is not high, the safety characteristics of industry of electric bicycle charger does not even require mandatory standards, resulting in some products even if qualified is not necessarily safe. For a comprehensive evaluation of safety hidden trouble of electric bicycle charger, Fujian Province Quality Inspection Institute recently organized a risk monitoring, in the monitoring of 30 batches of electric bicycle charger in the sample that do not meet the requirements of the 27 batches of samples, the unqualified rate was 90%.
[detection]
Power supply 1 minutes, charger smoke
Experts, electric bicycle charger is vulnerable to wear and tear, generally use a year to two years will be broken, need to change, many consumers will go directly to the repair site to buy. Original charger to 100 yuan, while the maintenance point may sell tens of dollars. From the results of this risk monitoring, 30 batches of samples have 27 batches of quality problems. The main problems are concentrated in the shell material, not flame retardant, no protective device, the use of inferior components and so on.
It is understood that this risk monitoring samples were to buy stores, customer service maintenance, network business and other channels to buy random electric bicycle entities, different companies, different brands, different models nationwide in 30 batches of products, of which 100 yuan of the following 27 batches, 3 batches of more than 100 yuan. In the charger type, the mainstream of the lead-acid battery charger products on the market, sampling 27 batches, lithium ion battery charger products 3 batches.
Reporters learned in the survey, the electric bicycle fire occurred mainly in the charging stage, charger overload, short-circuit and other failures are the main cause of fire. According to statistics, 75% electric car fire occurred during the charging process. Test personnel told reporters, when the failure, the charger should have internal protection device, can quickly fuse, in order to protect the line security.
In the laboratory, testing personnel first non normal work of the project test, according to "special requirements" battery charger safety of household and similar electrical appliances, the quality status of short circuit, reverse fault of the observed sample. The detection personnel will first a sample of positive and negative anti access AC power, and then to sample the continuous power supply, after 1 minutes and 06 seconds, the charger starts to smoke, while the charger is still not cut off the power supply after 3 minutes and 15 seconds, the charger cable suddenly fire burning.
After testing, 30 batches of samples in 23 batches of samples in the abnormal work project test, the circuit overheating, fire, explosion and other risks, the failure rate was 76%. Inspectors found after the technical analysis of each sample and the internal circuit board, most of the samples are Jerry: 30 batches of samples of 25 batches of samples without any protection device at the end of the AC power supply, a failure rate of 83.3%.