Do you know what is the SOH and SOC of the battery?
The health state of the battery is expressed by SOH, which is the full name of State of Health. If the battery is regarded as a container for storing electricity, SOC refers to how much available electric energy is stored in the container at a certain time (available electric energy here refers to the electric energy that can be used through discharge), while SOH is generally understood as how much the volume (not physical volume) of the container for storing available electric energy remains, that is, how much available electric energy it can store.
We believe that the health state of the battery SOH can be similar to the health state of people. The fresh batteries are in excellent health, which is equivalent to the young people with mature body tissues and organs. With the accumulation of service time and the impact of the environment, the internal structure of the battery gradually ages, and its health status slowly deteriorates. This process is similar to the process from maturity to aging. However, the health status of the battery is a comprehensive reflection of the overall status of the battery, which cannot be expressed solely by the residual charging capacity of the battery.
For example, in the same batch of backup batteries, the remaining usable capacity of a battery is reduced to 80% of the factory parameters due to the passivation of some active substances by substances involved in chemical reactions; When the internal grid of another battery is about to break and other irreparable structural damage occurs, the remaining usable capacity of the battery is also reduced to 80% of the factory parameters. The remaining usable capacity of these two batteries is the same, but their health status is completely different.
(1) The battery may still be able to maintain 80% or lower usable capacity for a long period of time after use.
(2) The battery may suddenly change from 80% of available capacity to completely unavailable in a short period of time.
For standby battery, the main test is its floating charge service life. Its normal state is always in floating charge state. When the floating charge voltage meets the manufacturer's recommended value, the battery's SOC is 100% even if it does not need to be measured. Of course, with the increase of service time, this indicator will decline to a certain extent. Of course, the service life of the battery will end, but conversely, the battery will be scrapped for various reasons, Its internal charging capacity is not necessarily lower than 80%. At this time, unless the two indicators are positive correlation when the internal resistance effect prevents the battery from discharging, the two indicators of other effects are irrelevant.
Considering the purpose of our assessment of battery health, we hope that our assessment of battery health can effectively guide our battery maintenance. Not only can we know whether the remaining available capacity of the battery can meet our demand for total temporary power consumption, but also we need to know when each single battery and battery pack need to be replaced and repaired, and it is more important to know the development trend of the battery's health status than the nuclear power capacity of the battery. Therefore, we believe that the monitoring and evaluation of battery health status should not only focus on the assessment of the proportion of the current available capacity of the battery, but also include the remaining service life of the battery and the healthy development trend.
--End--