Cnhl 3s lipo battery voltage characteristics

After understanding the structure principle of cnhl 3s lipo battery, the parameters of cnhl 3s lipo battery and its common concepts will be introduced one by one in future articles. The basic parameters of cnhl 3s lipo battery include terminal voltage, electromotive force, capacity, internal resistance, state of charge (SOC), depth of discharge (DOD), cycle life (Cycle Life) and self-discharge rate. On this basis, the characteristic analysis and description of the basic circuit of cnhl 3s lipo battery are carried out. Check it out with CNHL next.

Cnhl 3s lipo battery voltage characteristics

The terminal voltage of the cnhl 3s lipo battery refers to the potential difference between the positive and negative electrodes of the cnhl 3s lipo battery, which can be divided into open-circuit voltage (OCV) and working voltage according to the operation of the circuit. The open circuit voltage is the terminal voltage of the cnhl 3s lipo battery when it is not loaded and not connected to other power sources. In general, due to the internal resistance of the cnhl 3s lipo battery, the working voltage during discharge is lower than the open circuit voltage, and the working voltage during charging is higher than the open circuit voltage.

At the end of charging, the highest voltage allowed by the cnhl 3s lipo battery is called the charge cut-off voltage, and the lowest voltage allowed by the cnhl 3s lipo battery at the end of the discharge is called the discharge cut-off voltage. Beyond this range, the cnhl 3s lipo battery will suffer some irreversible damage. The cut-off voltage is an important safety indicator.
Working voltage refers to the potential difference between the positive electrode and the negative electrode when the cnhl 3s lipo battery is in working state. Due to the internal resistance of the cnhl 3s lipo battery, the operating voltage will be lower than the open circuit voltage. Similar to the rated voltage classification method, according to the working state, the cnhl 3s lipo battery voltage is divided into rated voltage, theoretical voltage, open circuit voltage and on-load working voltage.

The rated voltage is directly calibrated by the cnhl 3s lipo battery manufacturer after the cnhl 3s lipo battery is produced and before leaving the factory; the theoretical voltage is the theoretical value of the potential difference between the positive and negative electrodes after the internal chemical reaction of the cnhl 3s lipo battery is balanced, represented by E.
The open circuit voltage can be measured by directly connecting a multimeter or a voltmeter to the positive and negative terminals of the cnhl 3s lipo battery. The open circuit voltage is the voltage used for the equivalent model simulation.

Because the cnhl 3s lipo battery is not an ideal power supply, both the electrolyte and the electrode material have internal resistance, so the open circuit voltage is slightly less than the electromotive force. When the internal resistance is extremely small, the open circuit voltage of the cnhl 3s lipo battery can be treated as the electromotive force.
Under the actual working conditions, the working instantaneous voltage of cnhl 3s lipo battery is dynamic, and the phenomenon of overcharge and overdischarge cannot be avoided, and will cause damage to cnhl 3s lipo battery, so cnhl 3s lipo battery will be set in actual use.

Upper and lower limit voltage; upper and lower limit cut-off voltage need to be set reasonably. If the upper limit cut-off voltage is set too high, there may be potential safety hazards; if the setting is too low, the cnhl 3s lipo battery may not be fully charged. Similarly, if the lower limit cut-off voltage is set too low, there may be a potential safety hazard; but if the setting is too high, the efficiency of the cnhl 3s lipo battery will be too low. After research, when the discharge rate is high and the ambient temperature is low, when the cnhl 3s lipo battery is discharged and used, the discharge lower limit cut-off voltage can be set lower.

Cnhl 3s lipo battery open circuit voltage characteristics

The open circuit voltage of the cnhl 3s lipo battery is the voltage value across the cnhl 3s lipo battery after the cnhl 3s lipo battery is fully put on hold. The phenomenon that the cnhl 3s lipo battery has a current passing through it, causing the potential to deviate from the equilibrium potential, is called electrode polarization. Electrode polarization can be divided into concentration polarization and chemical polarization. Affected by the ohmic effect and polarization effect, the voltage of the cnhl 3s lipo battery fluctuates during use, so the acquisition of OCV usually requires the cnhl 3s lipo battery to be put on hold for a long enough time. Because there is a one-to-one correspondence between OCV and SOC, if you know the current OCV of cnhl 3s lipo battery, you can know its corresponding SOC, which is the so-called open circuit voltage method.

The following conclusions are drawn from the experiments
In the case of different discharge rates, with the prolongation of the discharge time of cnhl 3s lipo battery, the open circuit voltage shows a downward trend, and the higher the discharge rate, the more obvious the downward trend. At the same time, the higher the discharge rate, the lower the open circuit voltage.

Then, the open circuit voltage of the cnhl 3s lipo battery was sampled when it was stationary, and the changes of the static open circuit voltage at different discharge rates were obtained: at the end of the discharge period, the changes of the open circuit voltage at different discharge rates tended to be gentle. At the end of 2.0C rate discharge, the open circuit voltage is higher than 1.5C rate, and the open circuit voltage of 1.5C rate is higher than 1.0C. This is because the high rate discharge time is fast. Compared with the fast change of the low rate open circuit voltage, the voltage rebound of the cnhl 3s lipo battery at the end of the discharge is higher.

Influence of shelving time on open circuit voltage of cnhl 3s lipo battery

In order to study the open-circuit voltage variation characteristics of cnhl 3s lipo battery under different shelving times, the discharge shelving experiment of cnhl 3s lipo battery at a discharge rate of 1.5C was selected for analysis. The shelving time was set to 5min, 8min and 12min, and three different voltages were obtained. Variety

The three curves represent the voltage change curves under different shelf times, and the abscissa represents the discharge time. It can be seen from the figure that the voltage of the cnhl 3s lipo battery has a large change trend in the early stage of discharge, and is relatively flat in the later stage. In order to further understand the change of the open circuit voltage of cnhl 3s lipo battery under different shelving times, take the open circuit voltage of the cnhl 3s lipo battery when shelving, and draw and compare the open circuit voltages under three shelving times:

OCV1, OCV2 and OCV3 represent the open-circuit voltage change characteristic curve of cnhl 3s lipo battery under 5min, 8min and 12min rest time respectively. The abscissa represents the number of times the cnhl 3s lipo battery is put on hold during the discharge process. It can be seen from the figure that in the initial stage of discharge of the cnhl 3s lipo battery, the difference in the change of the open circuit voltage of the cnhl 3s lipo battery under the three kinds of shelving time is not obvious. cnhl 3s lipo battery open circuit voltage rises higher.
Well, the above is the whole content that CNHL brings to you today about the influence of cnhl 3s lipo battery terminal voltage, open circuit voltage and shelving time on the open circuit voltage of cnhl 3s lipo battery. I hope today's content can help you better understand cnhl 3s lipo battery, see you next issue.