To the equipment in order to provide sufficient voltage, lithium dell vostro 1310 battery, hp pavilion dm3 battery pack is usually made by a number of batteries in series, but if the battery capacity mismatch between the impact will be the capacity of the entire battery pack. To this end, we lost the need for a balanced allocation of the battery. This article discusses the concept of balanced battery and some attention.
Li-ion battery pack is usually one or more batteries in parallel, each battery pack by 3-4 in series constitute a battery. This combination can satisfy the laptop at the same time, medical equipment, testing equipment and industrial applications of the voltage and power requirements. However, the general configuration of this application does not usually exert their maximum effect, because if the capacity of a battery in series with other batteries do not match will reduce the capacity of the Toshiba laptop battery pack.
Battery capacity does not match, including state-of-charge (SOC) and capacity mismatch / energy (C / E) mismatch. In both cases, the total capacity of the battery pack can only reach the capacity of the weakest battery. In most cases, the mismatch caused by the battery of the reasons for process control and testing are imperfect means, rather than lithium-ion changes in their chemical properties. Prismatic lithium batteries (LiIonprismaticcell) required more time in the production of mechanical stress, the battery is more prone to the difference between. In addition, the lithium-ion toshiba pa3399u-1brs battery, toshiba pa3399u-1bas battery will be because the introduction of new technology and the emergence of differences between the battery.
Balanced use of the battery SOC and treatment techniques to address C / E mismatch problem, thereby improving the tandem performance of lithium-ion battery pack. Through the initial adjustment process in a balanced treatment of the cells can be corrected mismatch problem, since only in the charging process can be balanced, and the C / E mismatch must be sufficient discharge to a balanced process. Even though a battery manufacturer for their products in terms of possible defect rate is very low, but in order to avoid too short battery life, we still have the need for further quality assurance.
The definition of a balanced battery
Working voltage of 6V or more portable devices powered used in series, in which case the total battery pack voltage of the battery voltage of the series and. Portable computer from the battery pack is usually three or four batteries together in series, nominal voltage of 10.8V or 14.4V. In most such applications, a single series battery pack can not provide the energy needed. The biggest battery current (such as 18650) provides 2000mAh (milliamp hours) of energy, and the computer required 50-60Whr (5000-6000mAh) energy, it must give each series of three battery cells in parallel.
Battery balance refers to the series are different hp compaq 6510b battery, hp compaq 6910p battery (or battery) Use of differential current. Battery packs in series for each of the current battery is the same as usual, it is necessary to increase the extra battery pack and circuit components to achieve a balanced battery. Only when the battery pack in the battery are connected in series, at the same time series equal to or greater than the three-tier battery when the battery will consider the balance. When the battery pack to meet all batteries have the following two conditions, we achieve a balanced battery:
1. If all the capacity of the the same as when their relative status as charging the battery when the balanced implementation. SOC is usually the current capacity and nominal capacity expressed as a percentage, therefore, open circuit voltage (OCV) can be used as a measure of SOC. If a battery pack is not balanced all of the battery can be recharged through the differential reach full capacity (equilibrium point), they will be able to carry out the normal charge and discharge without any additional adjustment, this adjustment is usually a one-off. Users when using the new battery, it normally takes a long time called for charging batteries, in fact this process, including a full release – charge. So that the process to minimize the load and the longest battery and reduce battery requirements of a balanced circuit.
2. If the asus a32-f3 battery, asus a3000 battery capacity is different from the same when the SOC that they are balanced. However, SOC is a relative value, the absolute value of the capacity of each cell are different. Different in order to make the battery capacity SOC the same for each of the battery charge and discharge in series must be used when the difference current.
Normal charge and discharge time of the initial charge and discharge more quickly, and required greater current.
When the battery pack in the battery is not balanced, it will reduce the available capacity, serial battery pack in the battery capacity will determine the minimum of the total capacity battery pack. Imbalance in the battery pack, a battery or some other battery will still charge the maximum capacity has been achieved. In the discharge when the battery is not fully charged battery will be released than other electric end, the battery pack due to insufficient voltage to the supply of electricity in advance.
Typically, the satellite a65 series capacity of the differences between the less than 3%. If the lithium battery packs in series to a battery of sub-standard, or placed in the package too long ago, after the electricity at a voltage difference of up to 150mV, so that the total capacity of the battery pack dropped 13-18%.
SOC balanced treatment
If the battery pack in the battery capacity of all the same, we will deal with the use of SOC balance. When all the battery SOC value at the same time we believe that the satellite a60-662 battery are balanced.
A single battery charge status is defined as:
SOC = C / CTOTAL%
The capacity of a single cell is defined as:
C = (i × t) mAh
In order to determine the capacity of a hp pavilion dv2 battery, hp pavilion dv7 battery, hp pavilion dv6 battery , we have the battery fully discharge and then recharge, and recharge in the process of current measurement at different time until it reaches the open circuit voltage of 4.20V. The best performance of the battery status in the SOC for the 100%, SOC 50% of the OCV voltage is often referred to as VMID, its typical value of 3.67V.
In order to give a different battery capacity so that they achieve the same SOC, to ask some battery charge / discharge capacity than many other battery, which must use the current differential. We will call this process of capacity / energy maximization.
Capacity / energy to maximize
Capacity / energy to maximize the battery pack means that all the series is set to the same battery SOC, even if they are different capacity. Time management in all SOC, the battery pack to maximize the output energy. In order to maximize the output energy, all the batteries have to be full of electricity. That is, all the battery SOC must be 100%. If the battery capacity is different from a number of battery charge / discharge the battery will be more than any other. For example, suppose there is a battery pack of three batteries in series, C1> C2 = C3. Balance of the battery packs are the only way to give a higher capacity battery (C1) to impose a differential charge current.
Discharge the battery pack must also be the case, otherwise, when the battery capacity to meet the minimum turn-off voltage, the entire tecra 8100 battery pack will stop the discharge, while remaining battery capacity of the other, thus reduce the total capacity. The long run, the capacity of the smallest dell latitude e6400 battery, dell latitude e6500 battery performance will be a recession than any other battery faster, go through a number of charge / discharge cycle will accelerate the loss of capacity.
Through the matching series battery voltage, high-capacity toshiba pa3356u-1brs will draw more current. Discharge when consumed through a balanced number of extra voltage, in the final when all batteries have reached 0SOC when obtained from the battery pack relative to the total energy balance will increase the former.
Usually cylindrical lithium-ion battery (cylindricalcell) are usually of better quality control, battery capacity difference of no more than ± 3%. Basically, more precise input capacity, the difference does not exceed some mAs (milliampere seconds). Therefore, the capacity is also the basic accuracy of the absolute value, SOC at the difference within a few percentage points.
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