Fire safety categories. Li Bo - short biography of the poet Legislative support for fire safety inspections
Considered the greatest Chinese poet of all time, Li Po's life, in many ways typical of the scholar-poet of the Tang period, reveals the contradiction between Confucian duty and the Taoist ideal of renunciation of the world. The influence of Taoism permeates Li Bai's poems. Taoism during the era of Chinese rule Tang Dynasty, had no less influence on poetry than Confucian morality. Poets drew inspiration from his teaching. Taoism rejected the world and its honors, arguing that the truth can only be found by seclusion among the high mountains and wild forests, in the refuge of the immortals who have learned the secret of longevity and have found the Tao. The influence of Taoism on painting and poetry is enormous, although Confucians they didn't want to acknowledge him.
Although the poet Li Bo claimed descent from Li Gao himself, the ruler of the state of Western Liang in the 4th century and the ancestor of the ruling imperial house, distant kinship - if recognized by the emperor - did not give the poet's family any special privileges. Li Bo was born in Sichuan, most likely in 701, and his family was neither wealthy nor influential.
The great Chinese poet Li Bo
According to legend, Li Bo was a developed child and already at an early age he commented on Chinese classics. Perhaps such intensive study of Confucianism aroused his dislike, for in his youth he retired to Mount Minshan, where he studied Taoism with a hermit. In addition, Li Bo never made an attempt to obtain a position, because, having left the mountain, he did not go to the capital, but to travel around the country. In 724, while in Shandong, Li Bo created the "Six Idlers of the Bamboo Grove" society - a clear allusion to the Jin "Seven Sages of the Bamboo Grove".
Traveling around Henan and Shanxi, he once happened to help one poor warrior, who later saved the poet’s life. This warrior was none other than Guo Tzu-yi, after An Lushan rebellion who became the commander-in-chief of the army, the first minister of the empire and the patron of the Nestorian church in China. In 738 in Shandong, Li Bo met his great contemporary Du Fu, a poet equal and, according to many Chinese scholars, superior to Li Bo. They became friends, and their relationship is sung in many poems by both.
It was not until 742 that Li Bo first arrived in the Tang capital, Chang'an, where he was introduced to the court by a Taoist scholar whom he had met while traveling in Zhejiang. At that time, the beautiful imperial concubine Yang Guifei ruled the roost at court. Li Po, already a famous poet, was introduced to the emperor as an “exiled immortal”—a divine genius in the guise of a mortal—and Xuanzong immediately gave him a sinecure, obliging him to write poetry in honor of palace celebrations.
The only surviving calligraphic autograph of the poet Li Bo
It seems that this turned out to not be too burdensome, because Li Bo had enough time to indulge in wine drinking and enjoy the company of like-minded friends. They called themselves the "Eight Immortals of the Wine Cup" (or simply the "Eight Immortal Drunkards"). About these noble and educated people another great Chinese poet, Du Fu, wrote his magnificent poem in which Li Bo's distinguished friends are mentioned. Of these, Li Shiji was a minister until he resigned to hide from the slander of his rivals; Jin, Prince of Ruyang, belonged to the ruling house; Zui Zongzhi, a close friend of Li Bo, was a historian, and Zhang Xu was a calligrapher; Su Jin professed Buddhism, which did not prevent him from enjoying wine; He Zhizhang is a friend of Li Bo, who first brought him to the attention of the emperor.
For three years, Li Bo enjoyed the company of friends and the favor of the emperor himself. Xuanzong until, as a result of palace intrigues, he was forced to leave Chang'an. Slander and hostility came from both envious people and the powerful chief eunuch Gao Lishi. They say that once during a feast, a drunken Li Bo forced a eunuch to take off his boots - Gao Lishi could not forgive such humiliation. Li Bo wrote a poem in honor of the spring festival in the peony garden, and Gao Lishi whispered to Yang Guifei that Li Bo, supposedly praising her beauty, actually compared her to the "Flying Swallow" (Fei Yan), the beauty of the times Han dynasty. This would be a backhanded compliment, because Fei Yan deceived the emperor and was disgraced. Yang Guifei was indignant and demanded that the poet be expelled from the palace.
After leaving Chang'an, which was soon destined to suffer the fury of the warriors of An Lushan, Li Bo went to Shandong, where he studied Taoism at the residence of the "Tian Shi" (Heavenly Teacher), the spiritual head of the religion. Then the poet headed south again and reached Nanjing, where he met his old friend Zui Zongzhi, who had also been exiled. The An Lushan rebellion found the poet in Luoyang, from which he fled before the rebels captured the city. Li Bo ended up in the south, where he joined the headquarters of Li Ling, Prince of Yong, who organized resistance to An Lushan in the Yangtze Valley. Li Ling, however, tried to take advantage of the confusion that reigned after Xuanzong's abdication and proclaim himself emperor. His plan failed, the prince was stripped of his title, and Li Bo was imprisoned as his accomplice. Death awaited the poet, but he was saved by the intervention of Guo Ziyi, the commander-in-chief of the imperial troops, who had not forgotten the service rendered to him by the poet thirty years earlier.
The sentence was postponed, but Li Bo was exiled to the border county of Yelan (in present-day Guizhou Province). Slowly moving towards his place of exile, he traveled up the Yangtze, staying for long periods with friends. In three years, Li Bo only reached Wushan in Sichuan Province, and at that time a general amnesty was declared. The poet was already old, and the glory of Xuanzong's empire had faded. Li Bo sailed back to Taiping - Anhui Province, where his relative served as an official. There he died in 761. According to legend, Li Bo tried to hug the reflection of the moon in the waters of the Yangtze and drowned. At the site of his death, on the cliffs of Caishiji, 15 miles from Nanjing, a temple was erected.
To determine the list of necessary measures to comply with fire safety legislation, each room, structure, building or outdoor installation is assigned an object category fire safety. This classification is necessary so that the level of protective actions taken corresponds to the potential danger of an emergency situation. There are three types of objects:
- buildings or structures;
- premises;
- outdoor installations.
For more precise definition characteristics of each of them and the categories assigned to them, it is advisable to consider objects separately in groups.
How to determine the fire safety category of a room
All operated premises are divided into five types according to the degree of potential danger. They are determined by the gases, liquids or materials inside, as well as the technologies used in the case of industrial buildings. Below is a table of fire safety room categories containing descriptions and some examples of each.
| Room category | Basic characteristics and properties of gases, liquids and materials used or located in the premises in question | Example of a room |
| Category "A"- premises with increased fire and explosion hazard | Gases classified as flammable and flammable liquids (flammable liquids), which ignite with a flash point of up to 28 degrees. This results in a dangerous mixture that explodes when ignited with an outlet pressure of more than 5 kPa |
|
| Category "B"- premises classified as explosive and fire hazardous | Combustible fibers or dusts, flammable liquids with a flash point of more than 28 degrees, other flammable liquids that can form a dangerous mixture that explodes when ignited with an outlet pressure of more than 5 kPa |
|
| Category "B1-B4"– Premises classified as fire hazardous | Low-flammable and flammable liquids and solids, as well as materials (including fibers and dusts), ordinary substances and materials that, when mixed under natural conditions, only burn, provided that the premises in question do not belong to the categories “A” or “B” described above » |
|
| Category "G"- rooms with moderate fire hazard | Various substances classified as non-flammable, as well as those in a red-hot, hot or molten state, required by the conditions of the applicable technological processes. In this case, the processing or production of the final product involves the combustion or disposal of solids or liquids, as well as gases used as fuel |
|
| Category "D"- premises of reduced fire hazard | Various substances and materials that are non-flammable and are in the process of processing or cold storage |
|
Determining the fire safety category of a premises must be carried out by any business entity. Its result is reflected in the corresponding declaration drawn up upon commissioning of a constructed or reconstructed facility.
Categories of buildings and structures, as well as outdoor installations
In addition to the most commonly used definition of the fire hazard level of premises, similar classifications are used for buildings and structures, as well as outdoor installations. This is necessary to ensure that the fire prevention measures taken correspond to the degree of the potential threat.
| Category | Characteristics of a building without an automatic fire extinguishing system | Characteristics of the building on which the automatic fire extinguishing system is installed |
| A | Premises assigned category “A” occupy an area of 200 sq.m. or their share is higher than 5% of the entire building | Premises assigned to category “A” account for over 25% of the total area of the building or occupy from 1000 sq.m. |
| B | Premises assigned to categories “A” and “B” occupy an area of 200 sq.m. or their share is higher than 5% of the entire building. However, it does not belong to the previous group | Premises assigned to categories “A” and “B” account for over 25% of the total area of the building or occupy from 1000 sq.m. |
| IN | Premises assigned to categories “A”, “B” and “B1-B3” occupy an area of over 5% of the entire building. However, it does not belong to the two previous groups | Premises assigned to categories “A”, “B”, “B1-B3” account for over 25% of the total area of the building or occupy from 3500 sq.m. |
| G | Premises assigned to categories “A”, “B”, “B1-B3” and “D” occupy more than 5% of the total area of the building. However, it does not belong to the three previous groups | Premises assigned to categories “A”, “B”, “B1-B3” and “D” account for over 25% of the total area of the building or occupy from 5000 sq.m. |
| D | All other buildings and structures |
All other buildings and structures |
In a similar way, the calculation of categories of outdoor premises for fire safety, more often called installations, is carried out. It also divides all objects into five groups: from category “AN” - increased fire and explosion hazard to category “DN” - reduced fire hazard. The classification characteristics used in this case are almost identical to those used when grouping premises.
Designation of the fire safety category of premises, buildings and structures
As a result of the classification of protected objects, fire safety category signs are hung on each of them according to GOST. Their parameters are clearly defined by the Technical Regulations and must fully comply with them. There are two types of signs that are allowed for use: a red rectangle or a yellow triangle. Their sizes, colors used and the font of the inscriptions must correspond to those specified in the regulations.
When visiting any regulatory authority, the fire safety category sign for the premises (GOST R 12.4.026-2001) is one of the first to be checked, since its necessity is directly stated in all regulatory documents.
The TRIO company offers services for compiling fire declaration, training and certification of responsible employees of the enterprise, as well as carrying out design and installation work related to alarm and fire extinguishing systems. In addition, experienced and qualified specialists can perform any type of fire-retardant painting or impregnation of structures and materials.
Passing a fire safety check - step-by-step instructions
Fire safety inspection is an integral part of any type of business activity, no matter whether it is related to production or customer service. If you have premises used in business, then the fire inspector will definitely pay you a visit, and in some cases the very fact of carrying out your activities as an individual entrepreneur, LLC or JSC will depend on his decision. Therefore, before starting registration actions, be sure to familiarize yourself with the current fire safety regulations and try to comply with them already at the stage of creating production or organizing customer service.
Legislative support for fire safety inspections
Fire inspection inspections are regulated by No. 820-FZ “On State Fire Supervision” adopted in 2004. This regulatory act establishes the procedure for conducting inspections, the powers of inspectors, the rights and obligations of the person or organization being inspected, and the frequency of inspections. In accordance with this law, the fire inspectorate is obliged
- early notify the person being inspected of the fact of the upcoming inspection,
- and carry out the check itself no more than once every 2 years, with a duration of no more than 1 month (increasing these periods is possible only in exceptional cases).
More frequent visits by the inspector are permitted subject to monitoring of compliance with the inspection instructions regarding previously identified violations.
Based on another regulatory act - No. 294-FZ “On the protection of the rights of legal entities and individual entrepreneurs in the implementation of state. control..." public authorities, namely the General Prosecutor's Office and the monitoring organization itself, not only send a notification of inspections to the inspected person, but also publish in the public domain a plan for conducting them, including a plan for fire inspections.
In particular, a plan for inspections by regulatory legal entities is posted at http://plan.genproc.gov.ru/plan2018/. individuals and individual entrepreneurs for 2018. Any entrepreneur can enter the name of his organization (or individual entrepreneur), TIN and as a result find out whether a fire safety inspection will be carried out in the coming year.
Moratorium on scheduled inspections for small businesses
For the period 01.01.2016 - 31.12.2018, a moratorium on scheduled checks small businesses.
This prohibition has its exceptions - it does not apply to some individual entrepreneurs who work in particularly significant areas, for example:
- healthcare,
- education,
- social sphere,
- electric power industry and others.
In these organizations, scheduled inspections are allowed to be carried out two and three times every three years. The types of activities and the permissible frequency of inspections are determined by the Decree of the Government of the Russian Federation.
Despite the moratorium, all organizations, without exception, must strictly comply with all fire safety rules, from the design and construction of buildings and premises equipment to the availability of fire extinguishers in the required quantity and refilled, tested for functionality. Fire does not forgive negligence, laxity and simplification of everything! There are many tragic examples of this with mass casualties.
Step 1: Start Fire Check
So here we go fire safety inspections- this is receiving notification of the date of the inspectors’ visit, timing and procedure conducting an inspection. On the date specified in the notification, a fire inspector will come to you and the first thing he must do is show you written order fire chief (or his deputy).
Without presenting this document, no fire safety inspection can be carried out.
This document must contain
- information about the date of the inspection,
- her form,
- name of the inspected organization (or individual entrepreneur)
- and most importantly - about full name. and the rank of inspector.
You need to check all this information most carefully and if any discrepancies are found, demand that the document be replaced with a reliable one (for example, another inspector came to you). In addition, inspectors do not have the right to exceed the inspection periods stated in this order.
It would be a good idea to take a photocopy of the fire safety inspection order so that you can always refer to its contents and monitor the inspector’s actions for violations.
Step 2: Document Verification
After the fire inspector confirms his authority, he will first ask you to present documents that are necessary to comply with the fire safety regime of the controlled facility. The list of such documents may vary depending on the type of activity performed, the danger of production, the size of the premises, the number of employees, and so on. However, this list will definitely include:
- internal orders on fire safety measures (appointing responsible persons, conducting briefings, designating and equipping smoking areas);
- employee evacuation plan in case of fire (at the next step of the fire safety inspection, the inspector will definitely compare the presented plan with the actual plan of the building);
- a log of fire safety briefings (it is necessary that the log reflects the facts of regular briefings of all employees);
- agreements with organizations that install and conduct Maintenance fire alarms and fire extinguishing systems (in most cases, you will also be asked for copies of licenses of these organizations, which you must request before signing the relevant contracts);
- inspection reports of fire hydrants or water pipes (if your building has them, of course).
The need for fire alarm and fire extinguishing equipment in the premises depends on the area and specific use of the building. You can find out whether the building or premises you are using falls under current standards in the so-called NBP 110-03 “List of buildings, structures, premises and equipment subject to protection by automatic fire extinguishing installations and automatic fire alarms,” and download it at the end of this article.
Step 3: Checking the fire safety of the premises
After checking the documents, the inspector will begin a direct inspection of the building (or premises), during which he will check:
- compliance of the evacuation plan with the actual configuration of the premises;
- materials for finishing walls, floors and ceilings;
- presence, correct location and condition of emergency exits;
- the condition of the bars on the windows - they must be opened from the inside if all the windows in the room are barred;
- availability, quantity, condition and correct location of fire extinguishers and fire-fighting equipment;
- general state rooms, passages and escape routes for clutter;
- availability of information signs about evacuation routes, fire exits, designation of fire extinguishers and indication of the telephone number in case of fire;
- the presence and condition of fire warning systems (for those premises where more than 10 people work);
Step 4: Drawing up a fire safety inspection report
Based on the results of the control activities, the inspector must draw up a report on the fire safety inspection performed. Even during the process of inspecting the premises and checking documents, he may ask for explanations about any identified violations or shortcomings in the organization of fire safety. Taking these comments into account, and also based on generally accepted practice, a Fire Inspection Report is drawn up. As a rule, its preparation takes 2-3 days, after which the fire inspector presents it to the head of the legal entity being inspected. persons or individual entrepreneurs against signature.
IN Fire inspection report contains:
- information about the compiler (inspector) and the company being inspected, the date of the inspection;
- description of the current fire safety condition of the inspected premises;
- a list of identified violations with an appeal to current fire safety standards;
- measures of influence on the violator, the responsibility assigned to him;
- explanations of those responsible for the identified violations;
- notes on familiarization of the person being inspected (or his representative) with the act, as well as agreement or disagreement with its contents and information about violations;
- If serious violations are detected, protocols drawn up during the inspection of persons responsible for fire safety are attached to the report.
If you do not agree with the contents of the Fire Inspection Report, it does not record your explanations, you consider the violations or enforcement measures to be unfounded, then be sure to indicate “I do not agree” in the form of the report and argue in detail for your position.
From current practice, it can be argued that fire safety inspection is a serious matter, but rarely leads to serious liability in the event of the initial discovery of non-serious violations. In most cases, the fire inspector is limited to a warning and draws up an appropriate order with recommendations for eliminating the violation, as well as indicating the timing of checking compliance with these instructions. If you maliciously violate fire safety standards, or do not comply with the instructions of fire inspectors, then you cannot avoid administrative liability, and in extreme cases- and initiation of a criminal case.
Video on the topic
Battery production technologies do not stand still and gradually Ni-Cd (nickel-cadmium) and Ni-MH (nickel-metal hydride) batteries are being replaced on the market by batteries based on lithium technology. Lithium polymer (Li-Po) and lithium-ion (Li-ion) batteries are increasingly used as a power source in various electronic devices
Lithium- silver-white, soft and ductile metal, harder than sodium, but softer than lead. Lithium is the lightest metal in the world! Its density is 0.543 g/cm3. It can be processed by pressing and rolling. Lithium deposits are found in Russia, Argentina, Mexico, Afghanistan, Chile, USA, Canada, Brazil, Spain, Sweden, China, Australia, Zimbabwe and Congo
Excursion into history
The first experiments on creating lithium batteries began in 1912, but it was only six decades later, in the early 70s, that they were first introduced into household devices. Moreover, let me emphasize, these were just batteries. Subsequent attempts to develop lithium batteries (rechargeable batteries) failed due to safety concerns. Lithium, the lightest of all metals, has the greatest electrochemical potential and provides the greatest energy density. Batteries using lithium metal electrodes are characterized by high voltage, and excellent capacity. But as a result of numerous studies in the 80s, it was found that cyclic work (charge - discharge) lithium batteries leads to changes in the lithium electrode, as a result of which thermal stability decreases and there is a threat of the thermal state getting out of control. When this happens, the temperature of the element quickly approaches the melting point of lithium - and a violent reaction begins, igniting the gases released. For example, a large number of lithium mobile phone batteries supplied to Japan in 1991 were recalled after several fire incidents.
Because of lithium's inherent instability, researchers have turned their attention to non-metallic lithium batteries based on lithium ions. By playing around a little with energy density and taking some precautions when charging and discharging, they came up with safer so-called lithium-ion (Li-ion) batteries.
The energy density of Li-ion batteries is usually several times higher than that of standard NiCd and NiMH batteries. Thanks to the use of new active materials, this superiority is increasing every year. In addition to its large capacity, Li-ion batteries behave similarly to nickel batteries when discharged (their discharge characteristics are similar and differ only in voltage).
Today there are many varieties of Li-ion batteries, and you can talk for a long time about the advantages and disadvantages of one type or another, but you can distinguish them by appearance impossible. Therefore, we will note only those advantages and disadvantages that are characteristic of all types of these devices, and consider the reasons that led to the birth of lithium-polymer (Li-Po) batteries.
The Li-ion battery was good for everyone, but problems with ensuring the safety of its operation and high cost led scientists to create a lithium-polymer battery (Li-pol or Li-po).
Their main difference from Li-ion is reflected in the name and lies in the type of electrolyte used. Initially, in the 70s, a dry solid polymer electrolyte was used, similar to plastic film and not conducting electricity, but allowing the exchange of ions (electrically charged atoms or groups of atoms). The polymer electrolyte essentially replaces the traditional porous separator impregnated with electrolyte, so they have a flexible plastic shell, are lighter, have higher current output and can be used as power batteries for devices with powerful electric motors.
This design simplifies the production process, is characterized by higher safety and allows the production of thin batteries of any shape. The minimum thickness of the element is about one millimeter, so equipment developers are free to choose the shape, shape and size, even including its implementation in clothing fragments.
Main advantages
- Lithium-ion and lithium-polymer batteries with the same weight are superior in energy intensity to nickel (NiCd and Ni-MH) batteries
- Low self-discharge
- High voltage per cell (3.6-3.7V versus 1.2V-1.4 for NiCd and NiMH), which simplifies the design - often the battery consists of only one cell. Many manufacturers use just such a single-cell battery in various compact electronic devices (cell phones, communicators, navigators, etc.)
- Element thickness from 1 mm
- Possibility of obtaining very flexible forms
Flaws
- The battery is subject to aging, even if it is not used and just sitting on a shelf. For obvious reasons, manufacturers are silent about this problem. The clock starts ticking from the moment the batteries are produced at the factory, and the decrease in capacity is the result of an increase in internal resistance, which in turn is generated by oxidation of the electrolyte. Eventually, the internal resistance will reach a level where the battery can no longer supply the stored energy, even though there is enough energy in the battery. After two or three years, it often becomes unusable.
- Higher cost compared to NiCd and Ni-MH batteries
- When using lithium polymer batteries, there is always a risk of ignition, which can occur due to shorted contacts, improper charging, or mechanical damage to the battery. Since the combustion temperature of lithium is very high (several thousand degrees), it can ignite nearby objects and cause a fire.
Main characteristics of Li-Po batteries
As mentioned above, lithium-polymer batteries with the same weight are several times higher in energy intensity than NiCd and Ni-MH batteries. The service life of modern Li-Po batteries, as a rule, does not exceed 400-500 charge-discharge cycles. For comparison, the service life of modern Ni-MH batteries with low self-discharge is 1000-1500 cycles.
Technologies for the production of lithium batteries do not stand still and the above figures may lose relevance at any time, because Battery manufacturers are increasing their characteristics every month through the introduction of new technological processes for their production.
Of the variety of lithium-polymer batteries available for sale, two main groups can be distinguished: fast-discharge(Hi Discharge) and ordinary. They differ from each other in the maximum discharge current - it is indicated either in amperes or in units of battery capacity, designated by the letter “C”.
Application areas of Li-Po batteries
The use of Li-Po batteries allows you to solve two important problems - increase the operating time of devices and reduce battery weight
Regular Li-Po batteries are used as power sources in electronic devices with relatively low current consumption ( Cell phones, communicators, laptops, etc.).
Fast-discharge Lithium polymer batteries are often called " by force"- such batteries are used to power devices with high current consumption. A striking example Applications of “power” Li-Po batteries are radio-controlled models with electric motors and modern hybrid cars. It is in this market segment that the main competition between various manufacturers of Li-Po batteries takes place.
The only area where lithium-polymer batteries are still inferior to nickel ones is the area of super-high (40-50C) discharge currents. In terms of price, in terms of capacity, lithium polymer batteries cost about the same as NiMH. But competitors have already appeared in this market segment - (Li-Fe), the production technology of which is developing every day.
Charging Li-Po batteries
Most Li-Po batteries are charged using a fairly simple algorithm - from a constant voltage source of 4.20V/cell with a current limit of 1C (some models of modern power Li-Po batteries allow them to be charged with a current of 5C). The charge is considered complete when the current drops to 0.1-0.2C. Before switching to voltage stabilization mode at a current of 1C, the battery gains approximately 70-80% of its capacity. It takes about 1-2 hours to fully charge. The charger is subject to fairly stringent requirements for the accuracy of maintaining voltage at the end of the charge - no worse than 0.01 V/cell.
Of the chargers on the market, two main types can be distinguished - simple, non-“computer” chargers in the price category of $10-40, designed only for lithium batteries, and universal chargers in the price category of $80-400, designed to serve various types batteries.
The first ones, as a rule, have only an LED charge indication; the number of cans and the current in them are set using jumpers or by connecting the battery to various connectors on the charger. The advantage of such chargers is their low price. The main drawback is that some of these devices cannot correctly detect the end of the charge. They determine only the moment of transition from the current stabilization mode to the voltage stabilization mode, which is approximately 70-80% of the capacity.
The second group of chargers has much wider capabilities; as a rule, they all show the voltage, current, and capacity in mAh that the battery “accepted” during the charging process, which allows you to more accurately determine how charged the battery is. When using a charger, the most important thing is to correctly set the required number of cans in the battery and the charge current on the charger, which is usually 1C.
Li-Po Battery Operation and Precautions
It is safe to say that lithium-polymer batteries are the most “delicate” of those existing, i.e. require mandatory compliance with several simple rules. We list them in descending order of danger:
- Battery recharge - charge to a voltage exceeding 4.20V per cell
- Battery short circuit
- Discharge with currents exceeding the load capacity or leading to heating of the Li-Po battery above 60°C
- Discharge below 3V voltage per jar
- Battery heating above 60ºС
- Battery depressurization
- Storing in a discharged state
Failure to comply with the first three points leads to a fire, all others - to complete or partial loss of capacity
From all that has been said, the following conclusions can be drawn:
- To avoid a fire, you must have a normal charger and correctly set the number of cans to be charged on it.
- It is also necessary to use connectors that exclude the possibility of short-circuiting the battery and control the current consumed by the device in which the Li-Po battery is installed
- You need to be sure that your electronic device in which the battery is installed does not overheat. At +70ºС, a “chain reaction” begins in the battery, turning the energy stored in it into heat, the battery literally spreads, setting fire to everything that can burn
- If you short-circuit an almost discharged battery, there will be no fire; it will quietly and peacefully “die” due to overdischarge
- Monitor the voltage at the end of the battery discharge and be sure to turn it off after use
- Depressurization is also the reason for failure of lithium batteries. No air should get inside the element. This can happen if the outer protective package (the battery is sealed in a package like heat-shrink tubing) is damaged due to an impact, or damage with a sharp object, or if the battery terminal is severely overheated during soldering. Conclusion - do not drop from a great height and solder carefully
- Based on the manufacturers' recommendations, batteries should be stored in a 50-70% charged state, preferably in a cool place, at a temperature not exceeding 30°C. Storing in a discharged state has a negative impact on service life. Like all batteries, lithium polymer batteries have a small self-discharge.
Li-Po battery assembly
To obtain batteries with high current output or high capacity, parallel connection of batteries is used. If you buy a ready-made battery, then by the marking you can find out how many cans it contains and how they are connected. The letter P (parallel) after the number indicates the number of cans connected in parallel, and S (serial) - in series. For example, "Kokam 1500 3S2P" means a battery connected in series with three pairs of batteries, and each pair is formed by two batteries connected in parallel with a capacity of 1500 mAh, i.e. The battery capacity will be 3000 mAh (when connected in parallel, the capacity increases), and the voltage will be 3.7V x 3 = 11.1V.
If you buy batteries separately, then before connecting them into a battery you need to equalize their potentials, especially for the parallel connection option, since in this case one bank will begin to charge the other and the charging current may exceed 1C. It is advisable to discharge all purchased banks to 3V with a current of about 0.1-0.2C before connecting. The voltage must be monitored with a digital voltmeter with an accuracy of at least 0.5%. This will ensure reliable battery performance in the future.
It is also advisable to perform potential equalization (balancing) even on already assembled branded batteries before their first charge, since many companies that assemble cells into a battery do not balance them before assembly.
Due to the decrease in capacity as a result of operation, in no case should you add new banks in series with the old ones - the battery will be unbalanced.
Of course, you also cannot combine batteries of different, even similar capacities into a battery - for example, 1800 and 2000 mAh, and also use batteries from different manufacturers in one battery, since different internal resistance will lead to unbalance of the battery.
When soldering, you should be careful; you should not allow the terminals to overheat - this can break the seal and permanently “kill” a battery that has not yet been used. Some Li-Po batteries come with pieces of a textolite printed circuit board already soldered to the terminals for easy wiring. This adds excess weight- about 1 g per element, but it takes much longer to heat the places for soldering wires - fiberglass does not conduct heat well. Wires with connectors should be secured to the battery case, at least with tape, so as not to accidentally tear them off when connecting to the charger multiple times
Nuances Li-Po applications batteries
I will give a few more useful examples that follow from what was said earlier, but are not obvious at first glance...
Over the long life of a battery, its elements, due to the initial small dispersion of capacities, become unbalanced - some banks “age” earlier than others and lose their capacity faster. With a larger number of cans in the battery, the process goes faster. This leads to the following rule: it is necessary to monitor the capacity of each battery element.
If a battery is found in an assembly whose capacity differs from other elements by more than 15-20%, it is recommended to refuse to use the entire assembly, or to solder a battery with fewer elements from the remaining batteries.
Modern chargers have built-in balancers, which allow you to charge all elements in the battery separately under strict control. If Charger is not equipped with a balancer, it must be purchased separately and it is advisable to charge the batteries using it.
An external balancer is a small board connected to each bank, containing load resistors, a control circuit and an LED indicating that the voltage on a given bank has reached the level of 4.17-4.19V. When the voltage on a separate element exceeds the threshold of 4.17V, the balancer closes part of the current “to itself,” preventing the voltage from exceeding the critical threshold.
It should be added that the balancer does not prevent the overdischarge of some cells in an unbalanced battery; it only serves to protect against damage to the elements during charging and as a means of identifying “bad” elements in the battery.
The above applies to batteries composed of three or more elements; for two-can batteries, balancers, as a rule, are not used
According to numerous reviews, discharging lithium batteries to a voltage of 2.7-2.8V has a more detrimental effect on capacity than, for example, recharging to a voltage of 4.4V. It is especially harmful to store the battery in an over-discharged state.
There is an opinion that lithium-polymer batteries cannot be used at subzero temperatures. Indeed, in technical specifications The batteries have an operating range of 0-50°C (at 0°C 80% of the battery capacity is retained). But nevertheless, it is possible to use Li-Po batteries at subzero temperatures, about -10...-15°C. The point is that you don’t need to freeze the battery before use - put it in your pocket where it’s warm. And during use, the internal heat generation in the battery turns out to be this moment useful property, preventing the battery from freezing. Of course, the battery performance will be slightly lower than at normal temperatures.
Conclusion
Considering the pace at which technical progress in the field of electrochemistry is moving, it can be assumed that the future lies with lithium energy storage technologies, if they are not caught up fuel cells. Wait and see…
The article uses materials from articles by Sergei Potupchik and Vladimir Vasiliev
What is a fire safety declaration?
What information is included in the declaration?
Who prepares the declaration?
What happens if you don’t file a declaration?
What is a fire safety declaration
Warns
Alexey ANDREEV,
General Director of EAC Labor Technologies LLC (Moscow)
When submitting your declaration, do not forget to attach fire risk assessment calculations (if one was carried out) and a copy of the insurance policy (if the property is insured). Otherwise, the fire supervision department of the Ministry of Emergency Situations of Russia will refuse to register the document.
How to file a declaration yourself
If fire risk assessment is not required (For enterprises put into operation after the entry into force of Federal Law No. 123-FZ of July 22, 2008), then the declaration can be developed independently. In an organization, this can be done by a fire safety specialist or an employee responsible for fire safety. This does not require any licenses or accreditations. The main thing is to comply with the form of the document, which is established by order of the Ministry of Emergency Situations of Russia dated February 24, 2009 No. 91.
What happens if you don’t file a declaration?
If the inspection reveals the absence of a fire safety declaration, then the owner of the facility may be subject toadministrative liability in accordance with parts 1 and 2 of Article 20.4 of the Code of Administrative Offenses of the Russian Federation. For this and other violations, the official may be finedfor an amount from 6 to 15 thousand rubles, a legal entity will have to pay from 150 to 200 thousand rubles. Of course, the document is drawn up if the category of the premises in terms of fire and explosion hazard requires it.
In the absence of a declaration during an on-site inspection under a special fire regime, those responsible may be subject to an administrative fine in the following amounts: officials from 15 to 30 thousand rubles; legal entities— from 400 to 500 thousand rubles.
If this causes a person to suffer serious health damage, the offender faces:
- fine up to 80,000 rubles or in the amount wages or other income for six months;
- or restriction of freedom for up to three years;
- or imprisonment for up to three years with deprivation of the right to hold certain positions or engage in certain activities (Part 1 of Article 219 of the Criminal Code of the Russian Federation).
- If a person dies, the violator faces:
- restriction of freedom for up to five years;
- or imprisonment for a term of up to five years with deprivation of the right to hold certain positions or engage in certain activities (Part 2 of Article 219 of the Criminal Code of the Russian Federation).
Answers to your questions
For what period is the declaration developed?
Is it true that the declaration has a limited validity period? Then how often should you take it?
No that's not true. The declaration has no validity period; it must be submitted once during the entire existence of the object. The document will have to be revised and resubmitted if:
- information about the object will change, including its function (for example, a store will be converted into a restaurant);
- Fire safety requirements will change.
Do I need to approve the declaration?
With whom should the declaration be agreed upon and where should it be registered? Can registration be refused? What to do in such a situation?
The declaration does not need to be approved, but only registered with the territorial body of the state fire supervision of the Ministry of Emergency Situations of Russia. There are several main reasons for refusing to register a declaration:
- the document does not correspond to the form established by the order of the Ministry of Emergency Situations of Russia dated February 24, 2009 No. 91;
- the first section of the declaration is not completed without justifying the reason;
- a fire risk assessment report (if the magnitude of the risk is indicated) or a copy of the insurance contract (if the object is insured) is not attached;
- the declaration is not signed by the developer;
- incorrect information on the title page;
- The document is not stitched or sealed.
If rejected, the declaration will be returned to you with a written list of its shortcomings. The document will need to be redone and resubmitted for registration.
Who checks the availability of the declaration?
Who can check whether an organization has a fire safety declaration?
Check availabilityregistereddeclaration, as well as the correctness of its completion can be no employee onlystatefire supervision of the Ministry of Emergency Situations of Russia during a scheduled or unscheduled inspection.