Solar charge controller is an electronic device which is connected between solar pv panel and the battery. The main function of solar charge controller is to regulate battery charging process using power from the solar panel which includes multiple battery and panel protections for the system. Solar charge controllers are rated as per maximum input voltage and maximum charging current. These are further divided into two types based on technology used which is PWM or Pulse Width Modulation solar charge controller and MPPT or maximum power point tracker solar charge controller.

Monocrystalline solar panels are cut from a single source of silicon. The composition of these cells is purer since each cell is made from a single piece of silicon, thus the electrons have more space to flow making them more efficient. These are also more space efficient meaning smaller in size compared to polycrystalline solar panels. Monocrystalline solar panels also perform better in high heat and warmer temperatures. The performance over the period of it's life is also better than polycrystalline solar panels. Due to higher quality raw material used, the price of monocrystalline solar panel is also normally more than polycrystalline solar panel. Monocrystalline solar panels generally have a black coloured hue. Polycrystalline solar panel cells are blended from multiple silicon sources and are less efficient. Instead of using single silicon crystal, polycrystalline solar panels are made by blending multiple raw fragments of silicon together in square moulds and cooling them down to form wafers. Since the cells are made of multiple crystals, the electrons have relatively less space to flow. These are cheaper in cost but have lesser efficiency, performance life and are also happen to be bigger in size due to lesser efficiency compared to monocrystalline solar panel. The blending of several silicon layers gives polycrystalline solar panels an uneven blue coloured hue.

P-type cells are built with a silicon wafer doped with boron. As boron has one less electron than silicon, it produces a positively charged cell. P-type cells are affected by light-induced degradation (LID), due to which there is drop in output due to light exposure.

N-type cells are doped with phosphorus, which has one more electron than silicon, which makes the cell negatively charged. N-type cells are immune to boron-oxygen defects, hence are not affected by light-induced degradation (LID). This leads to much lesser degradation and hence retains higher efficiency over the life of the solar panel.

A battery management system (BMS) is an electronic system that manages various functions of a rechargeable battery (cell or battery pack) like high/low volatge protection, reverse polarity protection, monitoring its state, temperature compensation function etc. But what should be the most important aspect is cell or battery balancing. In this, each cell or series in the battery is monitored for it's individual charging & discharging ratio.
This is done is 2 ways-
Passive balancing: Here the energy is drawn from the most charged cell and dissipated as heat, usually through resistors.
Active balancing: Here energy is drawn from the most charged cell and transferred to the least charged cells, usually through capacitor-based, inductor-based or DC-DC converters across the pack.
Use of battery or cell balancing is a must while using any Lithium-ion or Lithium-ion phosphate/LiFePO4/LFP battery.