A solar street light is a street , parking lot or area light that is fully powered by solar energy. Using a battery plus photovoltaic panel, it charges during the day and turns on at night. They come in a large variety of shapes and sizes with optional features such as motion sensors and remote controls. They can be used for complete projects or to add lights in difficult places to wire.
Why choose solar street lights?
Compared to old-fashioned street lights, solar street lights have an edge on the competition because they offer the following perks:
Installation choice – install anywhere
Low maintenance
Easy installation
Better return on investment
Optimum lighting
Renewable energy source
Keeping this in mind, solar street lights seem like the most ideal replacement for regular street lights. As if that’s not enough, solar panels are currently becoming way less expensive, meaning that they’ll become more accessible for the average person. Not only that, but the efficiency rate of the solar street light’s battery panel is on the rise as well.
Types of solar street lights battery
Outdoor Solar street light battery equipment has a built-in type, Pole mount type, and buried type.
Built-in is the lithium battery pack integrated together into the light body; If external pole mount type is selected, it is better to install the equipment on the solar street light with a height of 6 meters, and there should be no climbing objects beside the solar-powered street light, also pay attention to anti-theft. If to choose the buried type, it is best to pay attention to anti-theft, waterproof, pouring cement ground to density, replaceability.
The battery is a very key component of the solar-powered street lights system, and also a major component of the solar-powered street lights system cost. At present, solar street lights mainly use Gel batteries and lithium batteries.
Gel batteries vs lithium batteries
Gel batteries belong to a development classification of lead-acid batteries. The method is to add a gelling agent in sulfuric acid to make the electro liquid of sulfuric acid become colloidal. Electrohydraulic colloidal batteries are commonly referred to as colloidal batteries.
The lithium battery is a kind of lithium metal or lithium alloy as a negative material, using a non-aqueous electrolyte solution, compared to a commonly used colloidal battery, the lithium battery is more environmentally friendly, lightweight and longer life, of course, the price of lithium battery will be slightly higher
By comparison, we can see why more and more solar street lights look less bulky than before, due to the use of lithium batteries. The lithium battery is used in solar street light system, and has the advantages that ordinary Gel solar street light battery does not have:
1 The charging and discharging system of lithium batteries generally adopts the integrated structure of lithium battery and controller, which is an energy storage battery system with no pollution.
2 According to the user’s demand, the remaining capacity, operation days and nights, weather conditions and other factors can be intelligently optimized and calculated, and the power level can be reasonably distributed. The functions of light control, time control, and memory storage, to ensure the intelligent setting of the solar street light system.
3 Lithium battery due to dry battery nature, more stable than Gel battery, safer.
4 Lithium battery weight is light, the same capacity specification weight is about 1/6-1/5 of the lead-acid Gel battery;
5 The environmental adaptability of lithium battery is stronger, the use of a wide temperature range can be used in the -20℃- 60℃ environment, after technical treatment, even can be used in the -45℃ environment, which also provides conditions for the promotion of solar street lights in cold areas.
Why lithium batteries are better ?
Lithium batteries (Li-ion, Lithium Battery): Lithium batteries are widely used because of their advantages of a lightweight, large capacity and no memory effect. The energy density of lithium batteries is very high, and their capacity is 1.5-2 times that of Ni-MH batteries of the same weight. (SYLVANIA solar street lights adopted Ni-MH batteries) Lithium also has a low self-discharge rate. In addition, lithium batteries have few “memory effects” and no toxic substances, which are also important reasons for their wide application.
Ternary Lithium batteries and LiFePO4 batteries are the two main types of Lithium Batteries that are used for Solar lighting products.
Ternary Lithium batteries vs LiFePO4 batteries:
1 The material system of a LiFePO4 battery and a ternary Lithium battery is different.
2 A LiFePO4 battery is a 3.2V voltage platform, with a cycle life of more than 2000 charges.
3 The ternary lithium battery is a 3.7V voltage platform, and the cycle life depends on different manufacturers, different models, and processes, and generally, it is 500-800 charge cycles.
4 LiFePO4 batteries offer better high-temperature performance, while ternary lithium batteries have better low-temperature performance.
5 LiFePO4 solar street light batteries are safer.
Further analysis of the two kinds of lithium batteries:
LiFePO4 batteries are characterized by high safety, high rate charge-discharge characteristics and long cycle life. The battery capacity is 80% of the initial capacity after 1600 cycles when the charging condition is 1C multiple charging to 3.65V, then the constant voltage is changed to 0.02C, and then the discharge voltage is 2.0V at 1C multiple charging to 2.0V cut-off voltage. LiFePO4 batteries also have stable charge-discharge characteristics and good fast charge characteristics. In addition to long life and excellent charge-discharge performance, the greatest advantage of LiFePO4 batteries is its safety. The chemical properties of liFePO4 batteries are stable and the high-temperature stability is good. The LiFePO4 batteries begin to decompose at 700-800 C, and will not release oxygen molecules in the face of impact, needling, short circuit and so on. It will not produce intense combustion and has high safety performance
Ternary lithium batteries refer to lithium batteries containing transition metal lithium-intercalated oxides containing nickel, cobalt and manganese, which can be expressed as LiMnxNiyCo1-x-yO2 (0 < x < 0.5, 0 < y < 0.5). This material combines the advantages of lithium cobalt oxide, lithium nickel oxide, and lithium manganate, and forms a ternary synergistic effect of three materials, whose comprehensive properties are superior to any single combination compound. Weight energy density can reach 200Wh/kg。
The safety of ternary lithium batteries is poor. The thermal stability of ternary lithium batteries is poor. They will decompose at 250-300C. When it encounters flammable electrolytes and carbon materials, decomposition will start at a point. The heat generated will further intensify the decomposition of the positive pole, and it will deflagrate in a very short time. In a car accident, the impact of external force can damage the battery diaphragm, which will lead to a short circuit, and the heat generated during the short circuit will cause the thermal temperature to rapidly rise to more than 300 C, creating the risk of spontaneous combustion. Therefore, for ternary lithium batteries, the battery management system and heat dissipation system are very important.
Conclusion:
Battery has a great influence on solar street lights. It is very important to choose a solar street light with a good battery. If you have any questions, please contact us. If you purchase Integrated solar LED street lights only marked “Lithium battery”, you have to know it uses LiFePO4 batteries or other Lithium batteries. Tachyonlight’s integrated solar street light’s battery is the best LiFePO4 battery, welcome to inquire.