Solar smartwatch:
Working principle: Solar smartwatch absorbs light energy (including sunlight and visible light such as daily lights) through the solar panel on the dial and converts it into electrical energy. The electrical energy is stored in the energy storage battery (usually lithium battery or other rechargeable battery) inside the watch, and then the battery provides power to the movement, display, sensor and other components of the watch to maintain the normal operation of the watch.
Advantages: It has a high endurance. As long as there is light, it can continuously replenish the power, reducing the trouble of frequent charging. It is very practical for people who often go out or are not convenient to charge at any time. Moreover, solar energy is a clean energy, and using solar smartwatches is also more environmentally friendly.
Technical challenges: The conversion efficiency of solar panels is a key issue. It is necessary to improve the conversion efficiency of solar energy as much as possible while ensuring the appearance design and wearing comfort of the watch to meet the power needs of the watch. In addition, in low-light environments or when there is insufficient indoor light, the effect of solar charging may be affected. The watch needs to have a better battery management system to ensure that it can still work normally when the power is low.
Representative products: For example, the solar smart wearable watch series launched by Garmin uses PowerGlass solar charging polar lens technology, which effectively converts light source into electrical energy while ensuring the clear visibility of the dial content.

Solar backpack:
Working principle: The surface of the solar backpack is usually inlaid with solar panels, which convert the absorbed solar energy into electrical energy and store the electrical energy in the battery inside the backpack through the built-in circuit system. The battery can provide charging services for various electronic devices such as mobile phones, tablets, digital cameras, etc. through output ports such as USB interfaces.
Advantages: For people who often travel, hike, camp and other outdoor activities, the solar backpack is a very practical equipment. It can use solar energy to charge electronic devices in the absence of a power socket, solving the problem of insufficient power of outdoor electronic devices. At the same time, the solar backpack has a large capacity and can meet the needs of carrying items when traveling.
Technical challenges: The solar backpack needs to ensure the durability and waterproofness of the solar panel to adapt to the complex outdoor environmental conditions. In addition, the weight and volume of the backpack are also factors that need to be considered. A backpack that is too heavy or too large will burden the user and affect the user experience.
Representative product: The back panel of the Hipack Solar backpack uses CIGS (copper indium gallium selenide) thin-film solar panels, which convert light energy into electrical energy and supply it to the built-in power bank. The direct output power exceeds 7W, which can charge a variety of USB devices. Its concave surface does not reflect light, can absorb more sunlight, and is waterproof and anti-fouling, breathable and comfortable.