After undergoing a period of time use, the original installation battery will have the situation which unavoidably standby time will reduce. Some users thought: “The depth  charging and discharging’s method can restore battery’s performance repeatedly, then length battery’s service life”, the author thought that this view is quite one-sided.

First, we must tell something about the battery type which uses by the notebook.. As we know, most of the notebook battery are supplied power with the nickel cadmium cell before 1995. This kind of battery, if the charging and discharging way is not correct, will have “the memory effect”, and thus reduce battery’s actual capacity. the depth charging and discharging method will eliminate this kind “the memory effect”. Along with the nickel hydrogen battery’s appearance, the battery capacity had the remarkable enhancement, but the ”memory effect” has not eliminated thoroughly.

In recent years, the lithium ion battery obtained the rapid popularization in the notebook. Because the lithium ion battery basically eliminated “the memory effect” question, therefore restores the battery performance with the method of the depth charging and discharging not to be suitable repeatedly. But the lithium ion battery will have the same problem of the reducing capacity, that’s because the original installation lithium ion battery uses the built-in battery management system .

Battery management: At present, most laptop battery used two kinds of chip level management system —- “the battery management” and “the charging and discharging control”. And “the battery management chip” placement in the notebook, it saves the lithium ion battery’s capacity, the operating temperature, the ID number, the charging and discharging condition, the charging and discharging accumulation number of times and so on. These data message need to be renew according to the actual situation unceasing floor brush in the use process. But the most main function of built-in “charging and discharging control chip”, is the surveillance, controls battery’s entire charging and discharging process and performs the record.

Charge: The lithium ion battery’s entire charging-up, can be divided into two stages —- “the constant flow rapid charge rate” and “the constant pressure electric current tapered charge”. “The constant flow rapid charge rate” refers to the time battery start to charge, the charging current fixes the charging voltage to follow battery’s terminal voltage gradually to elevate, until achieves the nominal voltage the charge way. After the battery has achieved the terminal voltage standard value, the control chip will change over to “the constant pressure electric current tapered charge” automatically, this time the charging voltage will not continue to elevate, but the charging current will follow the battery capacity to rise unceasingly decreases progressively gradually, and will achieve zero finally, that’s the battery’s complete charging-up.

Meanwhile, thest data that charging voltage, electric current, the time charging-up, will record in the battery “the charging and discharging control chip” in the memory. “the battery management chip” is takes these data through the sampling computation, and obtains the battery’s capacity, this is the Wh value which we can read in BatteryInformation.

Revision: After the notebook battery undergoes the multiple charging and discharging, its built-in chip’s charging and discharging data certainly will change. This time if “the battery management chip” does not have the opportunity to read new and complete data, it will calculate the battery capacity which will obtain to be certainly inaccurate, and bring the feeling that the battery’s capacity reduced to users, but in fact battery’s actual capacity not true reduction. Some notebook bringing charge management software’s principle of work, is refurbishing “the charging and discharging control chip” in memory’s data in the charging-up, then guarantees “the battery management chip” the computed result accuracy.

If you have observed notebook’s use instruction carefully, will discover a explanation that “the computer should make a complete charging and discharging operation to the notebook battery after using one month”. Its main purpose is revises the charging and discharging control chip with the depth charging and discharging way in register’s curve data, causes battery’s charge control and the nominal capacity and battery’s actual situation tallies, thus obtains the correct battery capacity value.