Battery Review and Tips

Engineers usually inexpensive multiple small capacity batteries in parallel to achieve the requirements of large UPS battery capacity, if used with poor battery performance and more uniform set of parallel, poor performance, low voltage battery pack would be a good battery performance group caused the collapse, leading to early failure of complete UPS battery system. Homogeneity of the current performance of the battery voltage is mainly based on the homogeneity measure, a variety of domestic standards, such as the Ministry of Information Industry, YD / T 799 – 1996 standard requirements for: 25 ℃ 2V battery cell when the entire group of not more than float voltage difference ± 50mV, open circuit voltage difference is less than ± 20mV; Ministry DL/T637–1997 standards are: 25 ℃, such as the battery system using 2V / cell, open circuit voltage of the highest and lowest section of the section were not more than 30mV, 6V / cell does not exceed 40mV, 12V / batteries no more than 60mV. The number of batteries in parallel groups generally should not exceed 4, in order to prevent the early failure of complete Dell inspiron 1520 Battery system, the choice of battery, it should be uniformity in terms of performance requested. When determining the battery model, the best in a UPS system requires manufacturers to provide the same batch of batteries, to reduce the performance differences. Similarly, different brand, or Condition of different batteries, because there is a big difference in performance, it is recommended not to mix. Finally, we must be pointed out that even if the choice of the appropriate VRLA, also need to make some necessary routine maintenance and management to avoid premature battery failure.

UPS Battery Maintenance

With the continuous development of science and technology, UPS is getting better performance, the average time between failures and longer, increasing the reliability of the machine. UPS batteries do a good job in the maintenance of consumables has become particularly important.

The initial charge new battery

The new battery after installation, generally charging for a longer period of time, charging power supply requirements in accordance with instructions for charging until the battery is fully charged, a discharge, the discharge again after charging, the purpose is to extend the battery life, improve the battery charge and discharge activity and characteristics.

Periodic charge and discharge

UPS internal battery power or make long-term idle in a floating state without long-term battery discharge, will cause the battery to lead sulfate in the number of cells adsorbed to the cathode surface, forming the so-called cathode plate of the “sulfate”, as lead sulfate is an insulator, its formation will have on the battery charge and discharge a very bad effect, because the formation of sulfate in the cathode plate the more the greater the internal resistance of batteries, battery charge and discharge performance can be more poor, leading to cell “aging”, “activity” down, so that the battery life shortened. Should be every 3 to 4 months to artificially interrupt the mains by or through the software / hardware control means to UPS’s rectifier / charger to shut down the state, so that the UPS battery discharge. For this to “activate” the battery and the Sony VGP-BPS3 battery discharge operation, the discharge time to control it in the normal discharge time of 1 / 3 to 1 / 4 is appropriate.

Depth of discharge is prohibited

Sealed maintenance-free battery life and is closely related to the depth of battery discharge. Depth of discharge is the process used by the user in the battery, the battery release accounted for when the security of its nominal capacity when the percentage of security. Depth of discharge will cause the internal battery plate surface sulfate, resulting in the battery internal resistance increases, serious cause individual cells appear “anti-pole” phenomenon and permanent damage to the battery. Seriously affect the depth of battery discharge the battery life, non-compelling, do not let the battery in deep discharge state.

Try to avoid over-current charge

Easily lead to over-current charging the battery positive and negative plates inside the curved surface of the electrode active material loss, resulting in decreased battery capacity available, the battery can cause serious damage to internal short-circuit plate.

Try to avoid over-voltage battery charging

Often leads to over-voltage charging battery electrolyte is contained in electrolytic separation of water into hydrogen and oxygen to escape, so that the battery life shortened.

Replacement activity declined, the battery internal resistance is too large

(1), with UPS power usage time, there is always part of the battery charge and discharge characteristics will gradually deteriorate, the terminal voltage decreased, the performance of the battery can no longer rely on UPS power to resolve the internal charging circuit, continue to use there will be risks, should be replaced.

(2), the battery internal resistance increases, with the normal charging voltage for charging the battery so that the battery can no longer recover its charge characteristics of the battery should be replaced. Battery internal resistance is generally 10 ~ 30mΩ, 200mΩ, such as the battery internal resistance than on the UPS will not be enough to maintain the normal operation of the CASIO QV-R3 battery internal resistance is too large to be replaced.

Avoid mixing old and new batteries or mix old and new batteries charge

Since the new battery internal resistance are relatively small, and old batteries have different degrees of increased resistance, when mixed with old and new batteries charged, the battery internal resistance of the old large, partial pressure will be relatively larger, easily phenomenon caused by over-voltage charging; and for a new battery, small internal resistance, charge voltage and small but the current is too large, and likely to cause over-current phenomenon, so the process of charging and discharging Hunchong old and new batteries should be avoided.

Battery use of the environment

Battery life is closely related with the ambient temperature, the battery at a low temperature, the battery in the zinc plate easily pulverized, lost electrical storage performance, resulting in permanent damage. Temperature is too high, the battery capacity will decline, a serious cause permanent damage. According to the TOSHIBA PA3465U-1BRS battery manufacturer’s technical specifications, the best use of the battery temperature is 20 ~ 25 ℃, the temperature range used to extend battery life.

A: UPS battery commonly used types of factors that affect battery life, different kinds of advantages and disadvantages of the battery:

The battery in the UPS application there are three: including open liquid lead acid batteries, maintenance-free batteries, nickel cadmium batteries. The UPS manufacturers are generally maintenance-free battery with pavilion zd8000 battery, following the main battery so as not to introduce three types of battery maintenance features:

1: Open the liquid lead-acid batteries: These batteries can be classified according to structure 8-10 years ,15-20 two-year life. Because the battery will produce corrosive sulfuric acid electrolyte gas, such batteries must be installed in the ventilation and the room away from the sophisticated electronic equipment, and battery room should be corrosion resistant ceramic tile laying.

Reasons due to evaporation, the proportion of open cells to be regularly measured, acid water. The battery can tolerate high temperature and pressure and deep discharge. Smoking and use the battery room should open the battery holder.

The klic-7001 Battery charge does not transport, and therefore must charge at the scene after the initial charging installation normally takes 55-90 hours.  Each section of the normal voltage of 2V, initial charging voltage is 2.6-2.7v.

2: maintenance-free battery: also known as VRLA batteries, in the use and maintenance must follow the following principles:

a: sealed battery can allow the operating range of 15 degrees -50 degrees, 5 degrees -35 degrees, but the use of extended battery life. Minus 15 degrees in the following chemical composition will change the battery can not charge. 20 degrees to 25 degrees in the range of use to a maximum of life. Batteries at low temperature operation will be long-lived but low capacity, high-temperature operation at a higher capacity but will be short-lived.

b: the relationship between en-el5 battery life and temperature can refer to the following rules, after the temperature exceeds 25 degrees Celsius, 8.3 degrees per high battery life will be reduced by half.

c: the design of maintenance-free battery float voltage to 2.3V / section. 12V battery is 13.8V. CSB recommended that each company section 2.25-2.3V. In the case of 120 cells in series, the temperature is above 25 degrees Celsius, the temperature is increased float voltage should be reduced once 3MV. The same temperature is increased by less than once in order to avoid charging voltage should be increased 3MV. Discharge termination voltage at full load (<30 minutes) to 1.67V under each section. In the case of the low discharge rate (low current discharge time) increased to 1.7V-1.8V to each section, APC SYMMETRA can adjust the charge voltage according to load.

d: after discharge within 72 hours if the battery does not recharge. Sulfate will be attached to the insulation charging plates, and damage the battery.

e: float or are charging the battery when the gas inside the battery into water electrolysis at the negative plate, so as to maintain the battery capacity and do not need additional water. However, the corrosion of the battery plate will reduce the Battery for Dell inspiron 1520 capacity.

f: battery separators life in the environment only when the temperature is 30-40 degrees 5-6 months. Prolonged storage of the battery must be recharged every 6 months time. Batteries should be stored in a dry cool environment. Environment at 20 degrees the battery maintenance 3-4% per month self-discharge rate and temperature changes.

g: maintenance-free batteries are equipped with safety valve, when the battery internal pressure increases to a certain extent can be automatically excluded from the excess gas valve, safety valve in the internal air pressure is restored automatically restored.

h: battery cycle life (charge and discharge cycles life) depends on the discharge rate, discharge depth, and recovery of the charge by means of which the most important factor is the depth of discharge. In the discharge rate and time certain, the more shallow depth of discharge, the longer the battery cycle life. Maintenance-free battery at 25 degrees under 100% deep discharge cycle life of about 200 times.

i: battery life is reached when the capacity fade performance of the internal short circuit, shell deformation, plate corrosion, open circuit voltage decreases.

j: IEEE defined as the capacity of the battery end of life less than 80% of the nominal capacity of AH. Nominal capacity and the actual backup time non-linear relationship, the corresponding reduction of 20% reserve capacity will reduce a lot of time. Some UPS manufacturers defined as the capacity of the battery end of life reduced to a nominal capacity of 50-60%.

k: the absolute prohibition of different sizes and different manufacturers of batteries together, otherwise it will reduce battery life.

l: If the two batteries in parallel, should ensure that the battery connection, the same bus impedance.

m: maintenance-free battery means you can not add liquid, but regular checks whether the shell cracks, leaks and other electrolytes is still necessary.

3: Ni-Cr Battery: This CR-V3 Battery is different from the lead-acid batteries produce hydrogen and oxygen during electrolysis without corrosive gas, which can be installed next to the electronic device. Water consumption and small, generally do not need maintenance. Normal life span of 20-25 years. Expensive than the previously mentioned battery. Initial installation costs about three times the lead-acid batteries. And high ambient temperature will not affect battery life, it will not be affected by environmental temperature is low battery capacity. Voltage of each section typically 1.2V, UPS batteries need to design because of application of such a high charger voltage.

II: advantages and disadvantages

An open lead-acid batteries:

Advantages: less investment, maintenance-free replacement BP-511 Battery  life than the long, low temperature requirements.

Disadvantages: maintenance of a more complex one that requires a special battery rooms, corrosive gas emissions must be on-site 50-90 hours of initial charging, need someone to maintain.

2: maintenance-free battery:

Advantages: no added liquid such as maintenance, transport in the fully charged state, no hand maintenance.

Disadvantages: not timely recovery of the charge will damage the battery, more sensitive to temperature, shorter life than lead-acid batteries expensive.

3: nickel cadmium batteries:

Advantages: low maintenance requirements, longer life expectancy, is not sensitive to temperature, no harmful gas emissions.

Disadvantages: the three most expensive batteries.

C: UPS battery commonly used in

Most use the computer center are generally maintenance-free batteries, maintenance more convenient, but also in need of the following:

1: to discharge inspiron 1520 battery pack every three to four months time, to prevent the electrode oxidation.

2: The ambient temperature should be maintained at 20-25 degrees.

3: The connection can not be too tight and too loose, need regular inspection.

4: After three years, the need for timely check and replace.