What is the battery charge controller. Li-Ion battery charge controller
The controllers themselves are useful devices. And to better understand this topic, it is necessary to work with a certain example. Therefore, we will consider the battery charge controller. What is it? How is it arranged? What features of the work exist?
What does the battery charge controller do?
It serves to monitor therestoration of energy losses and waste. First, it is engaged in monitoring the conversion of electrical energy into chemical energy, so that in the future, if necessary, supplying the required circuits or devices. It is not difficult to make a battery controller yourself. But it can also be extracted from power supplies that are out of order.
How the controller is arranged
Of course, there is no universal scheme. But many in their work use two poshodrachnye resistors, which regulate the upper and lower limit of voltage. When it goes beyond the specified limits, interaction with the relay windings begins, and it turns on. While it works, the voltage will not fall below a certain, technically predetermined level. Here we should talk about the fact that there is a different range of boundaries. So, for a battery, three, five, twelve, and fifteen volts can be set. Theoretically, everything depends on the hardware implementation. Let's look at how the battery charge controller works in different cases.
What are the types
It should be noted a significant variety, which can boast of the battery charge controllers. If we talk about their types, let's make a classification depending on the scope of application:
- For renewable energy sources.
- For household appliances.
- For mobile devices.
Of course, the species themselves are much larger. But since we consider the battery charge controller from a common point of view, then we will have enough of them. If we talk about those used for solar panels and windmills, then the upper limit of the voltage is usually 15 volts, while the lower limit is 12 V. The battery can generate in the standard mode 12 V. The power source is connected to it using normal closed relay contacts. What happens when the battery voltage exceeds the set value of 15 V? In such cases, the controller closes the relay contacts. As a result, the source of electricity from the battery is switched to a load ballast. It should be noted that he is not particularly fond of putting on solar panels because of certain side effects. But for wind generators they are mandatory. Household appliances and mobile devices have their own characteristics. Moreover, the battery charge controller of the tablet, touch and button cell phones are almost identical.
Let's take a look at the lithium-ion battery cell phone
If you crack any battery, you cannote that a small printed circuit board is soldered to the pins of the cell. It is called a protection scheme. The fact is that lithium-ion batteries require constant monitoring. A conventional controller circuit is a miniature circuit board on which a circuit made of SMD components is based. In turn, it is divided into two chips - one of them is the manager, and the other is the executive one. Let's talk in more detail about the second.
It is based on MOSFET transistors. Usually there are two. The chip itself can have 6 or 8 pins. For separate control of charge and discharge, the battery cells use two field-effect transistors, which are in the same housing. So, one of them can connect or disconnect the load. The second transistor does the same, but with a power source (which is the charger). Thanks to this implementation scheme, you can easily affect the battery performance. If desired, you can use it in another place. But it should be borne in mind that the circuit of the battery charge controller and it can only be applied to devices and elements that have a limited range of operation. More details about these features, we now talk.
Protection against overcharging
The point is that if the voltage of the lithiumbattery will exceed 4.2, then there may be overheating and even an explosion. For this purpose, elements of microcircuits are selected that will stop charging when this indicator is reached. And normally, until the voltage reaches a value of 4-4.1 V due to use or in the process of self-discharge, further charging will be impossible. This is an important function that is entrusted to the lithium battery charge controller.
Protection against overdischarge
When the voltage reaches the critically smallvalues that make the device's operation itself problematic (usually a range of 2.3-2.5V), then the corresponding MOSFET transistor is turned off, which is responsible for supplying current to the mobile. Then there is a transition to sleep with minimal consumption. And here there is a rather interesting aspect of the work. So, until the battery cell voltage becomes more than 2,9-3,1 V, the mobile device can not be turned on to work in the usual mode. Probably, such you could notice that when you connect the phone, it shows that charging is in progress, but it does not want to switch on and operate normally.
It should be noted that the charge controllerThe battery has a number of elements that must be protected from negative consequences. So, it's parasitic diodes that are placed in the field effect transistors, a charge detection circuit and a few more small additions. Oh, yes, and if it is possible to check the battery charge controller and find out the efficiency of the energy source, then its functioning can be restored even at "death". Of course, this means simply stopping work, not an explosion or melting. In this case, special devices can help, which carry out special "restorative" charging. Of course, they will work for a long time - the process can last for tens of hours, but after a successful completion the battery will work almost like a new one.
As you can see, the Li-Ion battery charge controllerplays an important role in ensuring the durability of mobile devices and positively affects their service life. Due to the simplicity of production, they can be found in virtually any phone or tablet. If there is a desire to see with your own eyes, and touch the Li-Ion battery charge controller and its contents with your hands, then during the analysis it should be remembered that the work is conducted with a chemical element in, so you should be very careful.