1. Photovoltaic panels and batteries must match.
Some manufacturers' solar lamps are labeled with 15A batteries, but they are equipped with 6V15W photovoltaic panels. I feel very speechless about this. The peak value of 6V15W photovoltaic panels can generate 2.5AH of electricity per hour, and the average sunshine duration in China is 4.5H. Is this configuration that 2.5AH photovoltaic panels can fully charge a 15A battery in 4.5h?
Some people may say, do not consider other time except 4.5 hours? After all, in addition to the peak value of 4.5 hours, electricity can also be generated at other times! Yes, there is nothing wrong with that statement. First, the efficiency of power generation at other times except peak time is very low; Secondly, the peak capacity conversion here is calculated based on 100% conversion. It is good that the process of photovoltaic power generation to charge the battery can reach 80% conversion. This is also why your 10000mA charging bank cannot charge the 2000mA mobile phone five times. As for the calculation here, it is not so detailed because we do not need to be very precise as engineers in this field.
2. The use of monocrystalline silicon photovoltaic panels does not mean that it is better than polycrystalline silicon.
Many businesses publicize that their photovoltaic panels for solar lamps are monocrystalline silicon and have high conversion efficiency, which is better than that of polycrystalline silicon. In terms of solar lamps, the quality of photovoltaic panels should be whether they can fully charge the battery of the lamps. If the photovoltaic panels are 6V15W and the power produced per hour is 2.5A, how is your monocrystalline silicon better than my polycrystalline silicon?
The competition between monocrystalline silicon and polycrystalline silicon has always existed. The efficiency of monocrystalline silicon is indeed a little higher than that of polycrystalline silicon in the laboratory test, but the gap between them is not large in the installed application. For solar lamps, whether single crystal or polycrystalline, it is good to use high-quality photovoltaic panels.
3. The more light beads, the higher the brightness?
More and more manufacturers are keen to make more and better lamp beads, because customers will think that the lamp beads are of sufficient materials and good quality when they see so many lamp beads. Anyway, the lamp beads are not valuable.
However, it is not the lamp beads but the batteries that maintain the brightness of the solar lamps. The lamps can work at the brightness of as many watts as the batteries can provide the lamps with power. Simply adding lamp beads does not increase brightness, but increases resistance and energy consumption.