201101500 六、發明說明： 【發明所屬之技術領域】 本發明係關於一種電池，特別關於一種太陽能電池。 【先前技術】 太陽能本身並無公害問題且取得容易，永不竭盡，故 太陽能成為重要替代性能源之一。較常應用太陽能之太陽 能電池是一種光電轉換元件，其經由太陽光照射後，把光 〇 能轉換成電能。 近年來，為提高發電效率，研發出一種聚光型太陽能 電池（Concentrating Photovoltaic, CPV)，其主要架構如圖 1所示。太陽能電池1包含一基板11、一太陽能電池封裝 體12以及一聚光透鏡13。其中，太陽能電池封裝體12設 置於基板11上，聚光透鏡13與基板11對向設置，當光線 經過聚光透鏡13時，會聚集至太陽能電池封裝體12。當 Q 光線被集中時，光線的強度會大幅增加，增加的幅度由聚 光透鏡13的聚光倍率所決定。由於太陽能電池封裝體12 吸收強度增強的光線，而能提升光電轉換效率及發電效 能。 然而，太陽能電池1在天氣狀況不佳時，大部分的光 線會被雲及水氣所散射，而這些被散射的光線由於並非平 行光，而無法藉由聚光透鏡13聚集至太陽能電池封裝體 12，使得光電轉換效率大幅降低。另外，由於太陽光的光 譜包含廣泛的波段，而太陽能電池封裝體12只能吸收其 201101500 中一範圍之波長的光線，使得光線利用率大大降低，這也 使得太陽能電池1之光電轉換效率無法提升。 因此，如何提供一種太陽能電池，能夠適合在各樣的 天氣狀況下使用，並且可接收不同波長範圍之光線，進而 提升光電轉換效率。 【發明内容】 有鑑於上述課題，本發明之目的為提供一種能夠適合 〇 在各樣的天氣狀況下使用，並且可接收不同波長範圍之光 線，進而提升光電轉換效率的太陽能電池。 為達上述目的，依據本發明之一種太陽能電池包含一 基板、一聚光型太陽能電池元件以及一薄膜太陽能電池元 件。基板係具有相對之一第一表面及一第二表面。聚光型 太陽能電池元件設置於第一表面。薄膜太陽能電池元件設 置於第二表面。 Q 承上所述，本發明之太陽能電池包含兩種太陽能電池 元件，其中入射光線之至少一部分能量可由聚光型太陽能 電池元件吸收，而入射光線之另一部分能量可由薄膜太陽 能電池元件吸收。當天氣晴朗時，大部分光線為平行光入 射，使得聚光型太陽能電池元件產生高效率的光電轉換效 率；而當天氣狀況不佳時，大部分光線為散射光，光線可 由薄膜太陽能電池元件吸收，因而能提升光電轉換效率。 此外，當聚光型太陽能電池元件及薄膜太陽能電池元件為 不同種類時，可分別吸收不同範圍之波長之光線，進而提 201101500 升光線利用率及光電轉換效率。此外，本發明之兩種太陽 能電池元件分別設置於基板之相對兩表面，而能夠大幅縮 小太陽能電池之尺寸，進而降低成本並提高產品競爭力。 【實施方式】 以下將參照相關圖式，說明依本發明較佳實施例之一 種太陽能電池。 請參照圖2所示，本發明第一實施例之一種太陽能電 ❹ 池2係包含一基板21、一聚光型太陽能電池元件22以及 一薄膜太陽能電池元件23。 基板21具有相對之一第一表面S1及一第二表面S2, 第一表面S1與一第二表面S2可實質相互平行。基板21 可為至少部分透光以讓光線通過，其中基板21之材質可 包含高分子材料，例如聚亞酿胺（Polyimide)或壓克力 (PMMA )、或石英、或玻璃、或金屬。本發明不限制基板 Q 21之形狀，其可例如為板狀、片狀或弧狀。另外，基板 21可為單一構件，或是由複數構件組裝而成，例如基板 21可由兩子基板相互疊設而成。其中，當基板21由複數 子基板疊設時，該等子基板可不相同。本實施例中，太陽 能電池2以具有一塊基板21為例。聚光型太陽能電池元 件22設置於第一表面S1。聚光型太陽能電池元件22之定 義為適合或易於以聚光方式接收光線之太陽能電池元 件。聚光型太陽能電池元件22可為晶粒或封裝體，當其 為晶粒時，可藉由打線接合（wire bonding )(如圖2所示） 201101500 及/或覆晶接合（flip chip)於基板21 ;當其為封裝體時， 可藉由表面接合（Surface-mount technology, SMT )設置於 基板21，以與基板21上之電路層電性連接。 另外’聚光型太陽能電池元件22可藉由雷射焊接 (laser welding)而覆晶接合於基板21。在此種情況下， 由於不是藉由打線接合，且雷射之加熱點尺寸可較小（例 如直徑可達到3mm)’因而可大幅提升晶粒之受光區的比 例，且當晶粒之尺寸越小時’可提升之比例越大。 〇 聚光型太陽能電池元件22之材質可包含單晶矽、或 單晶鍺（Ge )、或多晶石夕（multi-crystalline silicon )、或多 晶鍺、或複晶石夕（poly-silicon)或非晶石夕、或非晶錯、或 微晶石夕、或化合物半導體（例如瓜—V族或;[j — yj族）。其 中’多晶石夕係指由長晶製程而形成，複晶矽係指由非晶矽 以回火（annealing ) ‘私（例如藉由雷射回火）而形成。 在本實施例中，聚光型太陽能電池元件22係以化合物半 ◎導體為例，且化合物半導體可為多接面（multi-junction )。 薄膜太陽能電池元件23設置於第二表面S2。薄膜太 陽能電池元件23之材質可包含多晶矽、或多晶鍺、或複 晶矽、或非晶矽、或非晶鍺、或微晶矽、或化合物半導體、 或有機材料。在本實施例中，薄骐太陽能電池元件23係 以非晶矽為例。 聚光型太陽能電池元件22與薄膜太陽能電池元件23 係可為相同材料或不相同材料。當聚光型太陽能電池元件 22及薄膜太陽能電池元件23為不同材料時，可分別吸收 201101500 不同範圍之波長之光線，進而提升光線利用率及光電轉換 效率。例如，以純非晶石夕材料而言，其可吸收短波長（能 階約為1.7〜1.8eV)，而其若摻雜鍺可吸收長波長（能階約 為 1.4〜1.6 eV)。 另外，本實施例之聚光型太陽能電池元件22之面積 可小於薄膜太陽能電池元件23之面積的二分之一。藉由 兩者之面積的控制，可避免聚光型太陽能電池元件22吸 收過多散射光線而降低薄膜太陽能電池元件23之光電轉 〇 換效率。另外，聚光型太陽能電池元件22與薄膜太陽能 電池元件23之面積比例可依據所需產生電量而有所調 整，例如應用於大型電廠與家庭可有不同之比例。 在本實施例中，太陽能電池2可更包含一聚光元件 24，其係鄰設於聚光型太陽能電池元件22。聚光元件24 可為反射式或折射式，即可讓光線通過或反射。本實施例 之聚光元件24係以折射式為例，一入射光線之至少一部 Q 分能量係經由聚光元件24聚集至聚光型太陽能電池元件 22。聚光元件24的結構可包含至少一菲淫爾（Fresnel) 紋路、或至少一透鏡（lens )、或複數稜鏡（prism )、或一 反射面鏡（reflector )，於此係以菲淫爾紋路為例。當然， 若基板21上設置了複數聚光型太陽能電池元件22時，則 聚光元件24可具有複數對應設置的菲涅爾紋路。 太陽能電池2接收一入射光線，且入射光線之至少一 部分能量係經由聚光元件24聚集至聚光型太陽能電池元 件22,入射光線之另一部分能量係由薄膜太陽能電池元件 201101500 23吸收。如此一來，當天氣狀 為平行光（如圖2中的m5 人π刀入射先線係 π的黑色前碩所示），合 24聚集至聚光型太陽能電 ）由：先兀件 率而提升光電轉換效率；而者 且猎由提咼聚光倍 光線係為散射光，不易聚华況不佳時，部分入射 ,, 匆承集至聚光型太陽能電池元件22， 但仍能被薄膜太陽能電池元件201101500 VI. Description of the Invention: [Technical Field] The present invention relates to a battery, and more particularly to a solar battery. [Prior Art] Solar energy itself has no pollution problems and is easy to obtain, and it will never be exhausted. Therefore, solar energy has become one of the important alternative energy sources. A solar cell that uses solar energy more often is a photoelectric conversion element that converts light energy into electrical energy after being irradiated by sunlight. In recent years, in order to improve power generation efficiency, a Concentrating Photovoltaic (CPV) battery has been developed. The main structure is shown in Figure 1. The solar cell 1 includes a substrate 11, a solar cell package 12, and a collecting lens 13. The solar cell package 12 is disposed on the substrate 11, and the collecting lens 13 is disposed opposite to the substrate 11. When the light passes through the collecting lens 13, the solar cell package 12 is collected. When the Q light is concentrated, the intensity of the light is greatly increased, and the magnitude of the increase is determined by the concentration ratio of the condenser lens 13. Since the solar cell package 12 absorbs light of enhanced intensity, it can improve photoelectric conversion efficiency and power generation efficiency. However, when the weather condition of the solar cell 1 is poor, most of the light is scattered by the cloud and the water vapor, and the scattered light cannot be concentrated by the collecting lens 13 to the solar cell package because it is not parallel light. 12, the photoelectric conversion efficiency is greatly reduced. In addition, since the spectrum of sunlight contains a wide range of wavelengths, and the solar cell package 12 can only absorb light of a wavelength range of 201101500, the light utilization efficiency is greatly reduced, which also makes the photoelectric conversion efficiency of the solar cell 1 cannot be improved. . Therefore, how to provide a solar cell that can be used in various weather conditions and can receive light of different wavelength ranges, thereby improving photoelectric conversion efficiency. SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to provide a solar cell which can be used in various weather conditions and can receive light beams of different wavelength ranges, thereby improving photoelectric conversion efficiency. To achieve the above object, a solar cell according to the present invention comprises a substrate, a concentrating solar cell element, and a thin film solar cell element. The substrate has a first surface and a second surface. The concentrating solar cell element is disposed on the first surface. The thin film solar cell element is placed on the second surface. Q As described above, the solar cell of the present invention comprises two solar cell elements in which at least a portion of the energy of incident light is absorbed by the concentrating solar cell element, and another portion of the incident light energy is absorbed by the thin film solar cell element. When the weather is fine, most of the light is incident on parallel light, which makes the concentrating solar cell component produce high efficiency photoelectric conversion efficiency; when the weather is not good, most of the light is scattered light, and the light can be absorbed by the thin film solar cell component. Therefore, the photoelectric conversion efficiency can be improved. In addition, when the concentrating solar cell element and the thin film solar cell element are of different kinds, light of different wavelengths can be separately absorbed, thereby improving the light utilization rate and photoelectric conversion efficiency of 201101500 liters. In addition, the two solar cell elements of the present invention are respectively disposed on opposite surfaces of the substrate, and the size of the solar cell can be greatly reduced, thereby reducing cost and improving product competitiveness. [Embodiment] Hereinafter, a solar cell according to a preferred embodiment of the present invention will be described with reference to the related drawings. Referring to Fig. 2, a solar cell 2 according to a first embodiment of the present invention comprises a substrate 21, a concentrating solar cell element 22, and a thin film solar cell element 23. The substrate 21 has a first surface S1 and a second surface S2 opposite to each other, and the first surface S1 and the second surface S2 may be substantially parallel to each other. The substrate 21 may be at least partially transparent to allow light to pass therethrough, wherein the material of the substrate 21 may comprise a polymer material such as Polyimide or PMMA, or quartz, or glass, or metal. The present invention does not limit the shape of the substrate Q 21, which may be, for example, a plate shape, a sheet shape or an arc shape. Alternatively, the substrate 21 may be a single member or assembled from a plurality of members, for example, the substrate 21 may be formed by stacking two sub-substrates. Wherein, when the substrate 21 is stacked by a plurality of sub-substrates, the sub-substrates may be different. In the present embodiment, the solar cell 2 has a substrate 21 as an example. The concentrating solar cell element 22 is disposed on the first surface S1. The concentrating solar cell element 22 is defined as a solar cell element that is suitable or easy to receive light in a concentrating manner. The concentrating solar cell element 22 can be a die or a package. When it is a die, it can be bonded by wire bonding (as shown in FIG. 2) 201101500 and/or flip chip. The substrate 21; when it is a package, can be disposed on the substrate 21 by surface-mounting technology (SMT) to be electrically connected to the circuit layer on the substrate 21. Further, the concentrating solar cell element 22 can be flip-chip bonded to the substrate 21 by laser welding. In this case, since the wire is not joined by wire bonding, and the size of the heating spot of the laser can be small (for example, the diameter can be up to 3 mm), the proportion of the light receiving region of the crystal grain can be greatly increased, and the size of the crystal grain is increased. The greater the percentage of hours that can be increased. The material of the concentrating solar cell element 22 may comprise a single crystal germanium, or a single crystal germanium (Ge), or a poly-crystalline silicon, or a polycrystalline germanium, or a polycrystalline silicon. Or amorphous, or amorphous, or microcrystalline, or compound semiconductors (eg, melon-V or; [j-yj). Here, the 'polycrystalline stone' refers to the formation of a long crystal process, and the term "polycrystalline germanium" refers to the formation of an amorphous material by "annealing" (for example, by laser tempering). In the present embodiment, the concentrating solar cell element 22 is exemplified by a compound semiconductor conductor, and the compound semiconductor may be a multi-junction. The thin film solar cell element 23 is disposed on the second surface S2. The material of the thin film solar cell element 23 may comprise polycrystalline germanium, or polycrystalline germanium, or a germanium germanium, or an amorphous germanium, or an amorphous germanium, or a microcrystalline germanium, or a compound semiconductor, or an organic material. In the present embodiment, the thin tantalum solar cell element 23 is exemplified by amorphous germanium. The concentrating solar cell element 22 and the thin film solar cell element 23 may be the same material or different materials. When the concentrating solar cell element 22 and the thin film solar cell element 23 are made of different materials, light of different wavelengths of 201101500 can be separately absorbed, thereby improving light utilization efficiency and photoelectric conversion efficiency. For example, in the case of a pure amorphous material, it can absorb short wavelengths (energy order of about 1.7 to 1.8 eV), and if it is doped, it can absorb long wavelengths (energy order is about 1.4 to 1.6 eV). Further, the area of the concentrating solar cell element 22 of the present embodiment may be smaller than one-half of the area of the thin film solar cell element 23. By controlling the area of both, it is possible to prevent the concentrating solar cell element 22 from absorbing excessive scattered light and reducing the photoelectric conversion efficiency of the thin film solar cell element 23. Further, the area ratio of the concentrating solar cell element 22 to the thin film solar cell element 23 can be adjusted depending on the amount of electric power required, for example, it can be applied to a large power plant and a household in a different ratio. In the present embodiment, the solar cell 2 may further include a concentrating element 24 disposed adjacent to the concentrating solar cell element 22. The concentrating element 24 can be reflective or refractive, allowing light to pass or reflect. The concentrating element 24 of the present embodiment is exemplified by a refractive index, and at least one Q energy of an incident ray is concentrated to the concentrating solar cell element 22 via the condensing element 24. The structure of the concentrating element 24 may include at least one Fresnel pattern, or at least one lens, or plural prism, or a reflector, which is a Philippine The grain is an example. Of course, when the plurality of concentrating solar cell elements 22 are provided on the substrate 21, the concentrating elements 24 may have a Fresnel pattern corresponding to a plurality of settings. The solar cell 2 receives an incident light, and at least a portion of the energy of the incident light is concentrated to the concentrating solar cell element 22 via the concentrating element 24, and another portion of the incident light is absorbed by the thin film solar cell element 201101500 23. In this way, when the weather is parallel light (as shown in Figure 2, the m5 person π knife is incident on the front line π black front), the 24 is concentrated to the concentrating solar power): Improve the photoelectric conversion efficiency; while hunting and concentrating light is used as scattered light, when it is not easy to gather in a poor condition, part of the incident, rushed to the concentrating solar cell element 22, but still can be film Solar cell component
At 兀件23所吸收。藉由聚光型太 二…兀件22與薄膜太陽能電池元件23的搭配，太陽 ΟAt the element 23 is absorbed. With the concentrating type 兀 22 element 22 and the thin film solar cell element 23, the sun Ο
G 提升發電效率並延長發電時間，當然，若配合 使用追日裝置’則效果更佳。 請參照圖3所示，本發明第二實施例之一種 池3/系包含—基板31、—聚光型太陽能電池元件32以及 一薄膜太陽能電池元件33。 其中，太陽能電池3與太陽能電池2主要不同在於， 基板31係包含兩子基板3u、312相互疊設。子基板、 312可直接接觸而疊設，或是如圖3所示，兩子基板3n、 312之間具有一空腔（chamber)c。空腔c藉由封止件％ 而成為密閉空腔’封止件36可例如由膠體或固體所形成， 且可具有絕緣性。其中，聚光型太陽能電池元件32係設 置於子基板311 ’而薄膜太陽能電池元件33則設置於另一 子基板312。 太陽能電池3可更包含一液體35，其係充填於空腔 C。液體35可包含高導熱材質，例如石夕油、甘油、三甲苇 (溶劑）或是水。當然，液體35可依據實際情況而考量 絕緣性、腐蝕性、凝固點、熱膨脹係數等數值來選擇。藉 201101500 由液體35可大幅將太陽能電池元件32、33所產生的熱量 帶走，進而提升散熱效能，並延長太陽能電池3之壽命。 另外，液體35亦可讓光線折射，使穿透子基板311的光 線較均勻分佈，以增加薄膜太陽能電池元件33的整體光 線利用效率。 請參照圖4所示，太陽能電池3可更包含一透光框體 37，其係與聚光元件34連結，並與兩子基板之其中之一 連結，於此係以透光框體37與子基板311連結為例。其 ^ 中，透光框體37的材質可為玻璃或是透光的高分子材質。 一入射光線之至少一部分能量可經由透光框體37到達聚 光型太陽能電池元件32或薄膜太陽能電池元件33。由透 光框體37進入之侧邊光線可增加太陽能電池3之光線利 用率並提升其光電轉換效率。 請參照圖5所示，太陽能電池3 a與太陽能電池3主要 不同在於，透光框體37a係分別與聚光元件34及子基板 Q 312連結。而在圖6中，太陽能電池3b可更包含一承載體 38，其係設置於薄膜太陽能電池元件33，透光框體37b係 分別與聚光元件34及承載體38連結。 綜上所述，本發明之太陽能電池包含兩種太陽能電池 元件，其中入射光線之至少一部分能量可由聚光型太陽能 電池元件吸收，而入射光線之另一部分能量可由薄膜太陽 能電池元件吸收。當天氣晴朗時，大部分光線為平行光入 射，使得聚光型太陽能電池元件產生高效率的光電轉換效 率；而當天氣狀況不佳時，大部分光線為散射光，光線可 201101500 由薄膜太陽能電池元件吸收，因而依然能提升光電轉換效 率。此外，當聚光型太陽能電池元件及薄膜太陽能電池元 件為不同種類時，可分別吸收不同範圍之波長之光線，進 而提升光線利用率及光電轉換效率。此外，本發明之兩種 太陽能電池元件分別設置於基板之相對兩表面，而能夠大 幅縮小太陽能電池之尺寸，進而降低成本並提高產品競爭 力。 以上所述僅為舉例性，而非為限制性者。任何未脫離 ❹本發明之精神與範疇，而對其進行之等效修改或變更，均 應包含於後附之申請專利範圍中。 【圖式簡單說明】 圖1為一種習知太陽能電池的示意圖； 圖2為本發明第一較佳實施例之太陽能電池的示意 圖；以及 Q 圖3至圖6為本發明第二較佳實施例之太陽能電池的 不同示意圖。 【主要元件符號說明】 1、2、3、3a、3b :太陽能電池 1卜21、31 :基板 12 :太陽能電池封裝體 Π:聚光透鏡 22、32 :聚光型太陽能電池元件 10 201101500 23、 33 :薄膜太陽能電池元件 24、 34 :聚光元件 311、312 :子基板 35 :液體 36 :封止件 37、37a、37b :透光框體 38 :承載體 C :空腔 〇 si :第一表面 S2 :第二表面G Improves power generation efficiency and extends power generation time. Of course, it works better if you use the tracking device. Referring to Fig. 3, a cell 3 of the second embodiment of the present invention comprises a substrate 31, a concentrating solar cell element 32, and a thin film solar cell element 33. The solar cell 3 is mainly different from the solar cell 2 in that the substrate 31 includes two sub-substrates 3u and 312 which are stacked one on another. The sub-substrate, 312 may be stacked in direct contact or, as shown in FIG. 3, a chamber c between the two sub-substrates 3n, 312. The cavity c becomes a closed cavity by the sealing member %. The sealing member 36 can be formed, for example, of a colloid or a solid, and can have insulation. Among them, the concentrating solar cell element 32 is disposed on the sub-substrate 311', and the thin film solar cell element 33 is disposed on the other sub-substrate 312. The solar cell 3 may further comprise a liquid 35 which is filled in the cavity C. The liquid 35 may comprise a highly thermally conductive material such as lycopene, glycerin, trimethylhydrazine (solvent) or water. Of course, the liquid 35 can be selected depending on the actual conditions, such as insulation, corrosion, freezing point, and thermal expansion coefficient. By 201101500, the liquid 35 can greatly remove the heat generated by the solar cell elements 32, 33, thereby improving the heat dissipation performance and prolonging the life of the solar cell 3. Further, the liquid 35 can also refract light, so that the light passing through the sub-substrate 311 is more evenly distributed to increase the overall light utilization efficiency of the thin film solar cell element 33. As shown in FIG. 4, the solar cell 3 further includes a light-transmitting frame 37 coupled to the concentrating element 34 and coupled to one of the two sub-substrates, wherein the transparent frame 37 is The sub-substrate 311 is connected as an example. In the case of the light-transmitting frame 37, the material of the light-transmitting frame 37 may be glass or a light-transmitting polymer material. At least a portion of the energy of an incident ray may reach the concentrating solar cell element 32 or the thin film solar cell element 33 via the light transmissive frame 37. The side light entering from the light-transmitting frame 37 increases the light utilization rate of the solar cell 3 and enhances its photoelectric conversion efficiency. Referring to Fig. 5, the solar cell 3a is mainly different from the solar cell 3 in that the light-transmitting frame 37a is connected to the concentrating element 34 and the sub-substrate Q 312, respectively. In Fig. 6, the solar cell 3b may further include a carrier 38 which is disposed on the thin film solar cell element 33, and the light transmissive frame 37b is coupled to the concentrating element 34 and the carrier 38, respectively. In summary, the solar cell of the present invention comprises two solar cell elements, wherein at least a portion of the energy of the incident light is absorbed by the concentrating solar cell component, and another portion of the incident light energy is absorbed by the thin film solar cell component. When the weather is fine, most of the light is incident on parallel light, which makes the concentrating solar cell component produce high efficiency photoelectric conversion efficiency; when the weather is not good, most of the light is scattered light, the light can be 201101500 by thin film solar cell The components are absorbed and thus still improve the photoelectric conversion efficiency. In addition, when the concentrating solar cell element and the thin film solar cell element are of different kinds, light of different wavelengths can be separately absorbed, thereby improving light utilization efficiency and photoelectric conversion efficiency. In addition, the two solar cell elements of the present invention are respectively disposed on opposite surfaces of the substrate, and the size of the solar cell can be greatly reduced, thereby reducing cost and improving product competitiveness. The above is intended to be illustrative only and not limiting. Any equivalent modifications or alterations to the spirit and scope of the invention are intended to be included in the scope of the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic view of a conventional solar cell; FIG. 2 is a schematic view of a solar cell according to a first preferred embodiment of the present invention; and FIG. 3 to FIG. 6 are a second preferred embodiment of the present invention. Different schematic diagrams of solar cells. [Description of main component symbols] 1, 2, 3, 3a, 3b: solar cell 1 21, 31: substrate 12: solar cell package Π: concentrating lens 22, 32: concentrating solar cell element 10 201101500 23, 33: Thin film solar cell elements 24, 34: concentrating elements 311, 312: Sub-substrate 35: Liquid 36: Sealing members 37, 37a, 37b: Light-transmitting frame 38: Carrier C: Cavity 〇 si: First Surface S2: second surface
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