Guangzhou Anern Energy Technology Co., Ltd.

Self-Discharge Rate and Energy Density of Wall-Mounted Solar Battery

Nov 22, 2024
Table of Content [Hide]

    What is the Self-discharge Rate of Wall-mounted Solar Battery?


    Wall-mounted solar battery, after being charged, will exhibit a phenomenon where the capacity decreases during storage. This phenomenon is called self-discharge, also known as charge retention capability, which refers to the battery's ability to maintain stored electricity when not in use. The percentage of self-discharged electricity over a certain period in relation to the battery's total capacity is the "self-discharge rate." The self-discharge rate is usually calculated monthly. For example, if a battery with a capacity of 12Ah discharges 0.36Ah within a month, leaving 11.64Ah, then the self-discharge rate of this battery is 3%.


    Why Do Wall-mounted Solar Battery Self-discharge?


    The self-discharge phenomenon of batteries is related to various factors, which can be broadly divided into battery-intrinsic factors and environmental factors.


    Battery-intrinsic Factors


    During battery manufacturing, due to limitations in technology or environmental impacts, there will inevitably be some impurities on the materials inside the battery, such as the positive and negative plates and the separator. These impurities can cause a tiny short circuit between the positive and negative electrodes, leading to energy loss.


    Additionally, the natural decomposition of internal materials and poor insulation of the battery casing can also affect self-discharge.


    Environmental Factors


    During the storage of wall-mounted solar battery, environmental temperature, humidity, and dust can all affect the stability of the internal materials, causing energy loss. Moreover, in energy storage batteries, the BMS (Battery Management System) itself can also consume a small amount of battery energy.


    The self-discharge phenomenon is present in almost all batteries, but there's no need to worry. In reality, the self-discharge rate of batteries is very low. For lithium-ion batteries, the self-discharge rate is generally around 3% per month, which basically does not affect the normal use of the battery and does not cause any usage issues.


    What Is the Energy Density of Wall-mounted Solar Battery?


    Energy density refers to the amount of energy stored in a unit volume or mass of a substance. The energy density of a battery is defined similarly. It is expressed as the ratio of the battery's energy to its mass, with the unit being Wh/kg (watt-hours per kilogram; if measured by unit volume, the unit is watt-hours per liter).


    Its value indicates the ability of a wall-mounted solar battery to store electrical energy. Two batteries of equal mass, the one with higher energy density can store more electrical energy. Traditional lead-acid batteries have an energy density of about 40Wh/kg, while mainstream lithium batteries, depending on the specific battery materials used, can achieve energy densities between 100-350Wh/kg. The relatively new sodium batteries in the industry have an energy density ranging between 100-160Wh/kg.


    Advantages and Disadvantages of High-energy-density Wall-mounted Solar Battery


    Wall-mounted solar battery with higher energy density is smaller and lighter in size and volume at the same capacity, which makes their product more competitive in the market. Users evidently prefer batteries that are smaller, lighter, and can provide power for a longer duration rather than cumbersome batteries that take up a lot of space but provide only a small amount of energy. For lithium batteries, higher energy density often means longer service life, and lower self-discharge rate, and other advantages.


    However, more energy storage means that in the event of thermal runaway, the potential damage could be greater, posing serious safety risks. Therefore, higher standards for the BMS (Battery Management System) and overall safety design are required for high-energy-density batteries. The production cost, manufacturing process, and other factors also increase, making it harder for the final product to be competitively priced. Thus, the manufacture of a reasonable battery product often requires considering various factors like cost, performance, safety, and price.


    Andy Cao
    Andy Cao

    I’m Andy Cao, an energy engineer with over 16 years of hands-on experience in solar inverters, lithium battery energy storage, photovoltaic systems, and solar street lighting. I focus on real-world system performance and write to share practical, experience-based insights for professionals working in the solar energy industry.

    FAQ

    Are Anern products certified for international markets?

    Anern solar energy products comply with international certification standards such as ISO 9001, CE, TUV, FCC, and ROHS, supporting deployment in different regional markets.

    What markets does Anern serve?

    Anern supplies solar energy products and system solutions to customers in more than 200 countries and regions, supporting residential, commercial, industrial, and off-grid solar power projects.


    Anenr main serve markets:

    Middle East: Iraq, Lebanon, Syria, United Arab Emirates, Afghanistan, Yemen, Saudi Arabia

    Africa: Nigeria, Zambia, Kenya, Mali, Burkina Faso, South Africa, Egypt, Tanzania, Mozambique, DRC, Botswana, Ethiopia, Egypt, Morocco, Cameroon, Zimbabwe, Ghana, Algeria, Libya, Uganda

    Southeast Asia: Philippines, Indonesia, Malaysia, Myanmar, Thailand, Vietnam, Pakistan

    Americas: Colombia, Mexico, Brazil, Peru, Argentina, Chile, Honduras, Ecuador, United States

    Central Asia: Uzbekistan, Kazakhstan, Kyrgyzstan, Tajikistan

    Europe: Ukraine, Türkiye, Germany, Romania, Poland, France


    Note: If you want to distinguish by product, the above regions of the Middle East, Africa, Southeast Asia, and South America are all suitable for solar street lights and energy storage, while Central Asia and Europe are only suitable for solar energy storage products.

    Is Anern a solar inverter manufacturer or a system integrator?

    Anern operates as a solar energy solutions manufacturer, supplying solar inverters as part of integrated solar power systems that combine power conversion, energy storage, and system-level design for various solar applications.

    Does Anern manufacture lithium batteries for solar energy storage?

    Anern supplies lithium battery energy storage solutions designed for solar applications, including residential, commercial, and off-grid solar energy storage systems integrated with solar inverters.

    Is Anern involved in solar street lighting?

    Yes, Anern supplies solar street lighting solutions as part of its solar energy product portfolio, including integrated solar-powered lighting systems for public and infrastructure applications.

    References
    Please write down your whatsapp or other contact correctly
    Please write down your email address correctly
    Please write down your message
    Please fill up your requirement, our sales staff will contact you in time.Thank you!
    Please write down your whatsapp or other contact correctly
    Please write down your email address correctly
    Please write down your message
    TOP