battery mall

1 What is the Li-ion battery?
Li-ion is evolved from the lithium battery.Therefore, before introducing the Li-ion, we introduce the lithium battery first . For example, before the camera in button batteries are used in lithium batteries. Lithium battery cathode material is lithium metal,the anode is carbon. When charging the battery, the cathode of the battery will produce a lithium-ion, generation lithium-ion movement through the electrolyte to the cathode. As the carbon negative electrode were layered structure, it has a lot of micro, to the lithium ion on the anode embedded in the pores of the carbon layer, the more embedded lithium-ion are, the higher the charge capacity is. Similarly, when the battery discharges (ie, the process we use the battery), embedded in the negative ion of carbon layer extrusion, then movement back to positive. Back to the cathode of lithium-ion more higher discharge capacity. the battery capacity We usually refer to is the discharge capacity. In Li-ion charging and discharging process, the lithium ion is from the positive → negative → positive state of motion. Li-ion is like a rocking chair, both ends of the rocking chair are the bipolar battery, and lithium-ion rocking back and forth as players runs. Therefore, it is also known as Li-ion rocking chair battery.
2, which parts buildup the Li-ion battery?
(1) battery cover up and down (2) cathode – lithium cobalt oxide active material (3) diaphragm – a special kind of composite membrane
(4) negative – active substances for the carbon (5) organic electrolyte (6) battery cover (divided into two types of steel and aluminum)

For example, when the ambient temperature is below zero, the battery charge and discharge efficiency will be greatly reduced, so the charge rate will be very slow, after the battery is fully charged,the electric power supply time is only about 60% of the original, when the ambient temperature is below the minimum temperature limit (for example – 25 ℃), the battery electrode reaction rate is very low, even from the freezing point electrolyte, the battery performance may be only 10 percent, seriously affecting battery life.

3, the temperature above 60 ℃ may explode

And as the low temperature, if a portable battery works in the high temperature, it will also affect battery discharge efficiency,and the battery damage will be more serious. For example, the use of poor quality, or charger, charging time is too long, making the battery more heat, when the charge temperature exceeds the maximum limit temperature, it will destroy the cell with the chemical balance, causing the battery to material performance degradation and the battery life .

The same way, when the battery is discharging, that is the time we use laptops, because the internal short-circuit of the battery or battery design defects, if the temperature exceeds the maximum limits ,the battery capacity decreases, the using life reduces seriously and even the explosion may occurr, burning and other incidents.

In mobile use, the battery decides the notebook life time, as when the lithium-ion notebook batteries are under the non-normal temperatures, the temperature is too high or too low will bring a variety of issues, then how doees the temperature affects the laptop battery?

A ,0-40 ℃ is the most reasonable working environment

when the notebook is using, humidity, static electricity, temperature and so will affect it, but lithium-ion battery is most sensitive to the temperature, the temperature is too high or too low, will bring negative impact to varying degrees for the battery , usually, Lithium-ion battery limit ambient temperature is -20 ℃ ~ 60 ℃, while the 0 ℃ ~ 40 ℃ is the most reasonable working environment, but to play the performance potential of notebook batteries, 20 ℃ is the best use of the environment.

2, the temperature below -25 ℃ will affect the battery life

Although the laptop battery to allow be used in -20 ℃ environment, but this will affect the battery charge and discharge performance of a great general, the lower the ambient temperature is, the battery the activity of active material inside is lower , The higher electrolyte resistance and viscosity is, the ion diffusion is more difficult, the battery is not easy to charged and discharged.

E, over discharge
If the battery in the discharge process is more than termination voltage of the battery discharge , if it continues to discharge the battery which may cause inner pressure,the reversibility of positive and negative active material may be damaged, which may reduce the production capacity of the battery.

F, over charge
When the battery is charging, if it reaches the full status, it still continues to charge ,which may cause the battery inner pressure , the battery deformation, occurred overnight, and so on, battery performance will be decreased and damaged.

G, the energy density
The average release energy of battery volume unit and quality.
Generally in the same volume, the energy density of lithium-ion battery is 2.5 times than the nickel-cadmium battery, and is 1.8 times than the nickel-hydrogen battery , so in the case of equal capacity battery, lithium ion battery will be smaller and lighter than nickel-cadmium and nickel hydrogen battery .

H, self-discharge
Regardless of whether the battery is used , for various reasons, would give rise to the phenomenon of the loss of their power. If calculated in units of a month, then self-discharge of lithium-ion battery is about 1% -2%, Ni-MH battery self-discharge is about 3% -5%.

I, charge cycle life
Rechargeable batteries used in the repeated charge and discharge, the battery capacity back to the initial capacity decreased to 60-80%.

J, memory effect 
In the battery charge and discharge process, the battery plates produced in many small bubbles, these bubbles will reduce the size of the battery plates, but also indirectly affect battery capacity.

E, lead-acid batteries (Sealed)
Voltage: 2V service life: 200 ~ 300
Discharge temperature: 0 degrees to 45 degrees charging temperature: 0 degrees to 45 degrees
Notes:the volume and the weight is the largest.

The new battery charging Glossary
A, the charging rate (C-rate)

C is the first letter of Capacity,which is used to indicate the size of the value of the battery charge and discharge current.
For example:  when the rated capacity is 1100mAh, it means that 1100mAh (1C) discharge time can last 1 hour , such as the 200mA (0.2C) discharge time can last 5 hours , charge control can be calculated here.

B, termination voltage (Cut-off discharge voltage)
It means when the battery is discharging, the battery voltage drops to the lowest appropriate to continue the work of discharge voltage.
According to different battery types and different discharge conditions, the battery capacity and life requirements are also different, so the termination of the provisions of the battery discharge voltage is not the same.

C, open circuit voltage (Open circuit voltage OCV)
When the battery does not discharge ,the battery potential difference between the two poles is called the open circuit voltage.
Battery open circuit voltage, will by on the battery varies with the electrolyte material, if the battery positive and negative material is same , then no matter how big the size of the battery, the changes in geometry, from the open circuit voltage are the same.

D, discharge depth (Depth of discharge DOD)
during the process of the battery using,the battery’s capacity release percentage of its rated capacity is called depth of discharge.
The level of depth of discharge and secondary battery charge life has a deep relationship, when the secondary battery discharge depth is deeper, its charge life is shorter, so we should avoid depth of discharge when use the battery .

A, nickel-cadmium batteries (Ni-Cd)
Voltage: 1.2V service life: 500 times
Discharge temperature: -20 degrees to 60 degrees charging temperature: 0 degrees to 45 degrees
Notes: overcharge ability.

B, nickel-metal hydride battery (Ni-Mh)
Voltage: 1.2V service life: 1000
Discharge temperature: -10 degrees to 45 degrees charging temperature: 10 degrees to 45 degrees
Note: Currently, the maximum capacity is around 2100mAh.

C, lithium-ion battery (Li-lon)
Voltage: 3.6V service life: 500 times
Discharge temperature: -20 degrees to 60 degrees charging temperature: 0 degrees to 45 degrees
Note: weight is light 30% to 40% than Ni-MH battery , and the capacity is higher 60% than nickel-metal hydride batteries. But it is impatiant for over charge, if it is over charged ,the temperature is too high will cause destruction of the structure => explode.

D, lithium-polymer battery (Li-polymer)
Voltage: 3.7V service life: 500 times
Discharge temperature: -20 degrees to 60 degrees charging temperature: 0 degrees to 45 degrees
Note: The modified lithium, there is no battery fluid, which use polymer electrolyte, can be molded into shape, and it is steady than the lithium batteries.

Uninterruptible power supply (UPS) battery usually can use 3 to 5 years. Life expectancy depends on many factors, including the dosage (equipment must be in number of the battery-powered model ) and other environmental factors. Here are some principles  to ensure your equipment to extedn the battery life:

1.Ensure that your APC UPS stores in a cool, dry and ventilated place. Ideally, UPS placed the location of the temperature should not exceed 24 degrees Celsius. Meanwhile, for ventilation purposes, each side is left a reasonable amount about 1-2 inches, which is convenient for air circulation.

2. Every year, only when necessary for 1 to 2 times UPS run time calibration. Sometimes, you can perform run-time calibration to verify whether your running time is sufficient or not. However, the frequent implementation of run-time calibration will reduce the APC battery life expectancy.

3. Do not store the battery APC for a long time. The new battery can be stored for 6-12 months. After this time, you should use the battery as soon as possible, otherwise they will lose their large storage capacity. Does not recommend to store the used batteries.

4. Load does not exceed the rated capacity of UPS equipment 80%, as this would result in reduced running time. Load increases, the running time will be correspondingly reduced. If the power can not supply power ,the full load of the UPS will soon run out and the release of its battery charged, which will reduce the battery life expectancy. Note: To ensure longer battery run time, do the laser printer connected to the UPS backup battery socket. To ensure that laser printers use the “Surge only” outlet (using the appropriate model). For those who do not “Surge only” outlet of the UPS, the proposed laser printer connected to a separate APC surge suppressor.

the battery usage program

Most laptops are equipped with automatic functions of reduced frequency, the maximum benefit is to extend the using time of the battery. Many people who use the Celeron may have questions , our laptops do not have this feature, is it not naturally less power out? CPU power consumption is only a part, in fact, the the power consumption order should be : LCD> CPU (speed)> Graphics> Wireless LAN> CPU fan. In other words, in addition to CPU, we can start from the other side, the maximum reduction of electricity consumption.

There is a control panel in Windows XP, There is a power management option, the “power scheme”, set the LCD screen idle for 10 minutes to shut down which is the most reasonable and the hard disk will have to set more appropriate in more than 15 minutes. Instant boot disk does not need a certain power that frequently start and stop which will damage the hard disk greatly. Of course, you can also manually turn off the screen, most of the laptops are by fn + F3 function key to achieve.

Set shut down time of LCD and the hard drive. if you want to further save power, but also running on the system to adjust,  Windows XP can do this.Take the Thinkpad for example, most of the laptops have been built-in battery management software, general laptops will provide eight screen brightness adjustment, although the state can get the brightest best visual effect, but it is very, very power-hungry, so , edit a document or some other common application to adjust the screen brightness to the lower six or seven is best. At the same time, CPU can be set to the best battery performance, CPU fan running status can be set to “balanced” which is more reasonable.

Li-Ion battery cells suffer gradual, irreversible capacity loss with each discharge-charge cycle. Such aging occurs more rapidly as temperature and discharge loads increase.

The self-discharge rate of a Li-Ion battery is higher if the battery is left in an unpowered notebook.During prolonged storage or non-use, the battery charge will decrease below its recommended low-voltage level.

Leaving the battery in a depleted condition for an extended period accelerates the decrease in full charge capacity. Leaving the battery at a high level of charge in a high-temperature environment for extended periods (for example, running a notebook computer in a docking station under a heavy load) also accelerates the loss of capacity.

Running high-end applications using the battery accelerates the loss of capacity. For example, playing 3D games lowers full charge capacity faster than using word processing applications.

Time control:
To control the charging to the end by setting a certain charge time, generally in accordance with charging to 120% ~ 150% of the nominal capacity of the battery corresponds to the time required to control. Standard charge generally use the time control method, such as battery capacity in accordance with IEC standard test used the method of 0.1C charge 16 hours.

 -V control:
When the battery is fully charged, the battery voltage will reach a peak, and then voltage will drop. When the voltage drops to a certain value, then terminate charge.

The peak voltage control:
By detecting the battery voltage to determine the charge end, terminate charge when the voltage peak appears.

Temperature control:
In the battery charging process, the temperature will gradually rise. When fully charged, the battery temperature and ambient temperature will reach the biggest difference. When the difference match the maximum stop charging.

dT / dt control:
By detecting the battery temperature relative to the rate of change of charging time to determine the end of charge.

TCO control:
When the battery temperature increase to a certain value to stop charging.