In one aspect, a preparation method for a double-sided solar cell includes: preparing a semi-finished product of the double-sided solar cell, the semi-finished product including a silicon wafer, and a P-type doped layer, a front passivation layer, and a front anti-reflection layer that are sequentially formed on a front surface of the silicon wafer; providing an opening corresponding to a front finger on a front surface of the semi-finished product, the opening extending through the front anti-reflection layer and the front passivation layer in sequence and exposing a surface of the P-type doped layer; and coating a non-fire-through paste in contact with the P-type doped layer through the opening, sintering the paste, to form the front finger. This preparation method can increase the open circuit voltage of the double-sided solar cell, and improve the conversion efficiency of double-sided solar cell.

A solar cell includes a semiconducting substrate, a first emitter, an insulating layer, and a second emitter. The semiconducting substrate includes a first surface and a second surface, and includes a first region and a second region. The first region includes a first sub-region and a second sub-region. The first sub-region is in contact with the second region. The first direction is perpendicular to the thickness direction of the semiconducting substrate. The first emitter is disposed on the first surface and in the first region. The insulating layer is disposed on the first emitter and in the first sub-region. The second emitter is disposed on the first surface. The second emitter includes a first sub-emitter and a second sub-emitter. The first sub-emitter is located on the second region. The second sub-emitter is disposed on the insulating layer. Electrical conduction exists between the first emitter and the first sub-emitter.

A portable solar photovoltaic (PV) electricity generator module comprises a plurality of smart power slat (SPS) units, each SPS unit comprising a plurality of solar cells electrically connected together based on a specified cell interconnection design, and, at least one power maximizing integrated circuit collecting electricity generated by the plurality of solar cells. The plurality of SPS units are mechanically connected such that the SPS units can be retracted for volume compaction of the module, and can be expanded for increasing PV electricity generation by the module. The module can be used as part of an electric power supply with a maximum power point tracking (MPPT) power optimizer, storage battery and leads to connect to a load. The load can be AC or DC.

A bifacial solar cell includes a substrate; an emitter portion formed on a first surface of the substrate; a first insulating layer formed on the emitter portion; a plurality of first electrodes contacting the emitter portion through the first insulating layer and extended in a first direction; a plurality of first current collectors extended in a second direction crossing the first direction, wherein the plurality of first current collectors are electrically and physically connected to the plurality of first electrodes; a second insulating layer formed on a second surface of the substrate; a back surface field formed on the second surface of the substrate, and having an impurity concentration that is higher than an impurity concentration of the substrate; a plurality of second electrodes contacting the back surface field through the second insulating layer and extended in the first direction; and a plurality of second current collectors extended in the second direction.

Provided are an interdigitated back contact solar cell (10,a,b,c), comprising a monocrystalline, n-doped wafer (101), a first contact area (40) which is formed by a first stack on the surface of said monocrystalline wafer (101), said first stack comprising a thin silicon oxide layer (201) and a highly n-doped polycrystalline silicon layer (301), and a second contact area (20) which is formed by a second stack on the same surface of said monocrystalline wafer (101) as said first stack, said second stack comprising a thin silicon oxide layer (202) and a highly p-doped polycrystalline silicon layer (701), wherein a p-doped monocrystalline silicon region (801) is located in a gap (30) between said first contact area (40) and said second contact area (20) and a method for producing such an interdigitated back contact solar cell (10,a,b,c).

A bifacial solar cell is provided includes a substrate, a plurality of first electrodes provided on a first surface of the substrate in a first direction, a plurality of first current collectors provided on the first surface in a second direction crossing the first direction, wherein the plurality of first current collectors are electrically and physically connected to the plurality of first electrodes, a plurality of second electrodes provided on a second surface of the substrate in the first direction, and a plurality of second current collectors provided on the second surface in the second direction, the plurality of second current collectors being electrically and physically connected to the plurality of second electrodes, wherein the number of the plurality of second electrodes is more than the number of the plurality of first electrodes.

A bifacial solar cell includes a substrate of an n-type; an emitter layer positioned on a first surface of the substrate; a plurality of first electrodes locally positioned on the emitter layer and electrically connected to the emitter layer; a first passivation layer positioned on the emitter layer; a silicon oxide layer formed at an interface between the first passivation layer and the emitter layer, the silicon oxide layer having a thickness of about 1 nm to 3 nm; a first anti-reflection layer positioned on the first passivation layer; a plurality of back surface field layers locally positioned on a second surface of the substrate; a plurality of second electrodes respectively positioned on the plurality of back surface field layers and electrically connected to the plurality of back surface field layers; and a second passivation layer positioned on the second surface of the substrate.

A bifacial photovoltaic module with at least one bifacial solar cell is provided. The at least one bifacial solar cell includes a substrate with a front-side and a rear-side. The front-side is the light incident side and the rear-side has rear-side contact structure. The rear-side contact structure includes a plurality of electrically conductive contact fingers, which have a first metal, a plurality of solder pads electrically connected to the contact fingers. The solder pads have a top. The solder pads have a second metal, which is different from the first metal. The rear-side contact structure further includes several cell connectors electrically connected to the solder pads. The top of the solder pads is free from the contact fingers in an area along one direction. The cell connectors are disposed planar on or above this area.

Disclosed are a double-sided solar cell and a preparation method therefor. The double-sided solar cell comprises: a silicon wafer having a PN junction, and a front first silicon oxide layer, a front second silicon oxide layer, a front first nitrogen-containing silicon compound layer, a front second nitrogen-containing silicon compound layer, and a front third silicon oxide layer that are located on one side of an N-type layer of the silicon wafer and are sequentially stacked along a direction away from the silicon wafer; and a passivation layer, a back silicon oxide layer, a back first nitrogen-containing silicon compound layer, and a back second nitrogen-containing silicon compound layer that are located on one side of a P-type layer of the silicon wafer and are sequentially stacked along the direction away from the silicon wafer.

Semi-transparent photovoltaic module that comprises a front glass cover (1) and a rear glass cover (4), an array of bifacial cells (2) with a separation area between them and an array of rear refractive concentrators (3) that concentrate the rear light onto the rear surface of the bifacial cells. The invention is especially useful in photovoltaic agriculture applications for plantations that require a high level of insolation, or in integration into buildings that require high interior lighting.