On the restoration of VRLA technology
Introduction
With this information, energy, the rapid development of electronic technology, valve regulated lead acid batteries (VRLAB) has been widely used in telecommunications, electrical systems, communication networks, financial systems, systems transport, security systems, oil and coal, large-scale industrial and mining companies and others. Dell Latitude D510 battery Dell Latitude D520 battery
Compared with ordinary lead-acid batteries, VRLAB because technology is composed of oxygen-house, which has greatly facilitated the loss of electrolyte, so that it can operate in the state without long-term maintenance and was small, the stability of anti-explosion safety of tension, weight without pollution, light, HID performance, maintenance and small volume. However, widely used VRLAB Po batteries are maintenance-free as claimed, in fact, this statement is not scientific and accurate. Exactly speaking, VRLAB should be called “low-maintenance batteries,” is generally not necessary to add the acid and water, without adjusting the density of the electrolyte. Since the batteries are usually sufficient in the parallel rectifier device and impose a state of the small float, over time, the battery is activated materials within the electrolyte dry plate deformation, plate corrosion and sulfide and other exceptional circumstances, leading to battery capacity to reduce or even failure, when the power sector, most likely lead to power Dell Latitude D600 battery Dell Latitude D610 battery
VRLAB large facility in the country in the late 80s of last century, the initial installation of the battery products are mainly imported in the late 90s of last century, China does batteries used in large quantities in many areas . Most manufacturers claim that their VRLAB lifespan of 10 years, but in actual use in the battery life really that many 5-6 years, poor in 2-3 years, there will be decreased significantly the ability of this phenomenon. For this reason, it is necessary to seriously affect the life of the battery causes.
A battery of the recession and the reasons
With the rapid development of the telecommunications industry in Shaanxi, VRLAB increasingly used in remote and mountainous rural areas, due to a wide range of capabilities, lack of maintenance personnel expertise, combined with erratic power supply , frequent power outages. Because the battery to occur in the context of various defects, in particular, to the full depth of discharge of the battery is often early battery failure. The main form of battery failure are: deformation of the positive plate corrosion, the positive active material softening and shedding, surface plates of lead or sulphate to produce velvet, short-circuits in the crystal. Dell Latitude D620 battery Dell Latitude D800 battery
VRLAB another compound in order to achieve greater efficiency, and more generally for the poor hydraulic design of the acid to control the capacity of the battery, the design theory or Pu laboratory results are good, but in hands of users, often premature failure, particularly in the case of frequent power failure, battery discharge, reducing the density hydraulic l.06/cm3 below, or even lower, causing concentration of the electrolyte free of lead has increased dramatically, it causes the root causes of battery failure.
2 factors affect battery life
The battery is a chemical power, its structure is very similar across South cathode, anode, electrolyte, consisting of isolated objects and containers, which only the negative poles of the active material and electrolyte the chemical reaction, the cell produces a current plays a dominant role.
VRLAB real life impact on many factors play a major role is the following.
2.1 float voltage setting on the life of the battery
Tensioning load on the battery life have a considerable influence, float g unreasonable voltage mainly affects the pool and the battery does Tuen plate grid corrosion rate of emissions. Dell Latitude D810 battery Dell Latitude D820 battery
2.2 The method of equalizing the costs of battery life
load balanced enough to avoid some of the capacity of batteries end pressure for conduct incompatible with the extra power. At equilibrium of gas charge more than a few times when the floating charge, if the charging time is too long, do not load pressure is too high to prevent excessive gas affect the effectiveness of recombination of oxygen, increase water loss, but also on the board of directors increased the rate of corrosion at the gate damage the battery.
2.3 Over Discharge
Battery against discharge is an important factor affecting the life of the battery. This happens primarily in the converter in case of battery failure, the load during the period. When the battery is to discharge lead acid battery inside a substantial lead are adsorbed on the cathode surface to form a stack which is just very positive “sulfate” is a type of insulating lead sulphate. The formation of lead sulfate cathode resistance over most of the battery, the battery can load and unload the worst SUI, the faster decline in the capacity of the battery, the shorter its life. Dell Latitude D830 battery Dell Studio 14 battery
2.4 Conditions on the operating life of VRLA batteries
The operating conditions of the battery life of the battery have a major impact. If the long-term use at high temperatures, increasing the temperature by 10 ℃, the battery life of about halfway.
The float is run the best conditions of battery operation, battery is fully charged condition, in these conditions to achieve the battery life longer.
Discharge time of the battery frequently and often without the power of the situation, but also for the depth of discharge, so that power losses in the state of battery time, internal cooking plate, resulting in a rapid decrease capacity, the battery back.
3 behind the activated cells repair
3.l internal battery reaction principle
electrolyte VRLAB PbSO4 always saturated PbSO4 is insoluble in the electrolyte in the dissolution and precipitation of lead sulphate in the balance, the beginning of the density of the acid battery discharge l.30g/cm3 general, the concentration of 39.1% weight percent, with the increasing depth of discharge, the mass percent concentration decreased to 8.7% or less, the density l.06g/cm3 following, and sometimes lowest close to neutrality. Dell Studio 1435 battery Dell Studio 1436 battery
Discharge charge the battery, if not quickly or not fully charged, the discharge will be produced by crystallization of lead sulfate crystals of lead sulfate irreversible, leading to recovery of the plates, the battery back.
3.2 Activation battery
battery charge and discharge process is responsible for pulses in one or more stages, in strict compliance with the battery charging system load curve, charging mode is designed for “→ constant (geese are fully stable value ) will flow Yajian (automatic identification) constant current discharge of style tri-band so cool and if the electrolyte. This method is ideal, you can remove sulfur.
Pulse battery discharge current for cyclic and constant, the crystals of lead sulfate of its internal activation, increase the density and mass percent concentration of sulfuric acid with the activation of the repair of deeper, so that the concentration of the mass density of battery acid, 39 per cent. l%, the electrolyte in the dissolution and precipitation of lead sulfate in equilibrium. Solubility in the solution to comply with the rule that Dell Studio 14 battery Dell Studio 15 battery
Battery has been fully restored, the battery life was extended for one or two cycles.
3.3 lagging seriously behind the agreement of the battery
Hardening plate severe electrolyte dry or very short circuit, open circuit the battery (serious resistance is too high, the tension is high or zero) must be replaced immediately. City short of 2V battery connected to the urgency of the battery.
3.4 repair activated cell
Not all of them behind the battery can be repaired, leading to many factors behind the battery, usually under-7, that is, plate expansion, plaque corrosion, passivation of the electrode material loss effective electrolyte dry plate short, very hardening Plate. 4 can not be repaired before and after the repairable 3 feet. One factor behind the battery plate drying led to the largest proportion, up to 90%. Therefore, the ability of the rated capacity of 40% to 80% behind the battery is the relatively high success rate fixed by the test, which determines the rate of 95% or more, and the ability of the rated capacity of 40% or less behind the success rate of cellular repair relatively low. dell latitude d820 battery dell latitude d830 battery
4 on the activation of the battery repair battery charger
need to activate battery repeatedly allow discharge, charge the battery for a delay, sometimes does not go for it, then the maintenance personnel by improving the method of charging voltage to the load charge voltage as high as possible, the higher, it can repair the battery. This is a misunderstanding. This is because the decomposition of water is O2 = 2H2O ↑ 4 H + +4 e-
If the voltage is too high, overcharging, the result can be two types of the following situations.
1) Reaction of internal oxygen complex in a timely manner to the compound of oxygen, there will plenty of oxygen, hydrogen released from the exhaust valve (or even can cause a battery explosion) so that the reduction capacities.
2) positive response to PbSO4 2 H2O = PB02 e. +3 H + + HS04-2 anode in the battery, lead alloy and direct contact activity of lead dioxide, and soaked in sulfuric acid solution, each with a sulfuric acid solution are built on different equilibrium electrode potential. In the state of battery charge. Cathode reaction because the evolution of oxygen. The water is consumed, H + increases, leading to increased acidity near the cathode, the acceleration of the plate corrosion, causing the plate to the severe corrosion, debris Er Shi battery repair have been unable to secure the battery into the battery. To this end, recommendations are generally not sufficient when the voltage exceeds 2.35V. dell latitude d800 battery dell latitude d810 battery
5 Conclusion
How to prolong the battery supply power and life, improve resource utilization, is our common concern, but not the truth behind the battery can be repaired. Technology of lead acid batteries, but the benefits of the repair are beyond doubt.