Hydrogen passivation technology for improving light failure problem of mono-crystalline solar cell

Technical Field

The invention relates to single-crystal solar cell manufacturing field, in particular to a method for improving single-crystal solar cell of the light decay process.

Background Art

In the new energy era, photovoltaic power generation is a clean, safe, convenient and has an important position of clean energy and the most important one of the renewable energy technologies. The present China is strong support for the development of the photovoltaic industry, battery production and assembly rise year by year. Therefore, in-depth research and use of solar energy, to relieve the resource crisis, the improvement of the ecological environment has a very important meaning.

The present mainstream market photovoltaic cell is boron-doped P-type silicon-based solar cell, the current technology in the production process of the silicon body can not completely remove the packing position, this causes the polycrystalline silicon solar cell for a long time under the illumination efficiency of the phenomenon has obvious attenuation. Single crystal solar cell is used as the best efficiency of one of the photovoltaic cell, this kind of light attenuation is very obvious, generally reach 2.5 - 3%, very harmful to the maintained stable power generation, has severely limited the development of the photovoltaic industry. So how to maintain through the process optimization in the efficiency of access to lower the light decay of become the focus of single crystal cell industrial production.

Content of the invention

The invention Patent is to solve the technical problem, provides a method for improving the light decay single crystal solar cell of the hydrogen passivation process.

A method for improving the light decay single crystal solar cell of the hydrogen passivation process, which comprises a DC power supply 1, single crystal cell 2, the conductive plate 3, the vent 4, ventilating plate 5, ; characterized in that the DC power supply 1 through the wire with the single crystal cell 2 on said conductive separator 3 is electrically connected with the; single crystal cell 2 is externally provided with the external temperature control system; said external temperature control system comprises an air hole 4, ventilating plate 5 form; said single crystal cell 2 are on two sides of ventilation with air holes 5; the above ventilation plate 5 are installed on one side of a vent hole 4, the above-mentioned aluminum plate 5 are vent holes 4 connected, it is through gas flow meter to adjust the blowing flow and the heating of the cell or maintain the temperature to the temperature of the temperature.

The hydrogen passivation process is crystal cell 2 surface SiN: H film layer in the H, through the control of the direct current power supply 1 is applied to the single crystal on the battery current, single crystal cell 2 and the temperature of the power-on time, to adjust the silicon in the substrate of the B - O defect in high and low between, at the same time utilize the current to adjust to the same H , thereby achieving the decay rate of the battery; the hydrogen passivation process can also be applied to such single crystal and polycrystalline solar cell, and such single crystal and polycrystalline solar cell to improve the light decay in the process will not reduce the photoelectric conversion efficiency of the battery.

Characterized in that the conductive partition walls 3 and the ventilation plate 5 for the aluminum plate, copper plate, the round saw, a lead plate, a zinc plate in.

Characterized in that the conductive partition walls 3 and the ventilation plate 5 has a thickness of 3 - 7 mm.

A method for improving the light decay single crystal solar cell of the hydrogen passivation process, characterized in that the process is mainly divided into four stages, as follows:

1st stage: the single crystal cell stack connected in series, the same specification to stack the single crystal cell in series with, the cell number is 100 - 400 sheet;

2nd stage: a direct current power source are connected to the single crystal cell anode (P-type end), cathode is connected to the negative pole of the battery (N-type end), to the battery applying forward current is applied 1 - 5 A; external temperature control system is stable and the battery temperature is 100 - 150 °C; maintain 10 - 40 minutes;

3rd stage: after the end of the 2nd stage, the battery applying forward current is applied 7 - 12 A; external temperature control system is stable and the battery temperature is 150 - 200 °C; maintain 5 - 30 minutes;

4th stage: after the end of the 3rd stage, the battery applying forward current is applied 5 - 10 A; external temperature control system is stable and the battery temperature is 140 - 180 °C; 30 - 60 min after passes through the cooling system to the room temperature the follow-up process.

Further, the process is divided into four stages, as follows:

1st stage: the single crystal cell stack connected in series, the same specification to stack the single crystal cell in series with, the cell number is 100 - 400 sheet;

2nd stage: a direct current power source are connected to the single crystal cell anode (P-type end), cathode is connected to the negative pole of the battery (N-type end), to the battery applying forward current is applied 3 - 5 A; external temperature control system is stable and the battery temperature is 130 - 140 °C; maintain the 20 - 30 minutes;

3rd stage: after the end of the 2nd stage, the battery applying forward current is applied 9 - 11 A; external temperature control system is stable and the battery temperature is 180 - 190 °C; maintain 10 - 20 minutes;

4th stage: after the end of the 3rd stage, the battery applying forward current is applied 6 - 8 A; external temperature control system is stable and the battery temperature is 160 - 175 °C; maintaining the 45 - 55 min passes through the cooling system to the room temperature the follow-up process.

Wherein the single crystal cell stack connected in series mode is to adopt the every 8 - 12 cell with H-shaped and a cross-connect in series to stack a.

Wherein said process of single crystal cell in the standard test conditions for the light decay: illumination power is 1000 - 3000 W, test time is 5 - 12 hours.

Wherein said process of single crystal cell in the light decay under standard test conditions for the photoelectric conversion efficiency is calculated -0.07% -0.02%, optical attenuation is 0.2% -1.5%.

The invention relates to process the beneficial effect:

1. By the electric current in the control process, the temperature and time, to adjust the SiN: H H to the battery body in the movement of the B - O and other harmful complex defect passivation, to ensure that the loss of efficiency<0.07% of the cases, reach the light decay is reduced to 1.5% of effect within, improve the long-term stability of the photovoltaic cell power generation capacity;

2. The process of the invention is not limited to the single-crystal solar cell, also includes a diamond-like single crystal and polycrystalline solar cell, and the polycrystalline solar cell obtained on the light decay of improvement will not reduce the photoelectric conversion efficiency of the battery;

3. The invention single crystal cell per 8 - 12 cell with H-shaped and a cross to stack in series mode, can effectively improve the cell in the process of charging local overheating and the heat dissipation problem of non-uniform;

4. The invention selected process temperature, current and time is easy to reach and control, method is simple, and the effect is obvious, and can be compatible with industrial production, has high utility value.

Description of drawings

Figure 1: the embodiment of the invention method legend

Attached Figure captions: DC power supply 1, single crystal cell 2, the conductive plate 3, the vent 4, ventilating plate 5.

Specific embodiment:

Embodiment a:

As shown in Figure 1, for improving single crystal solar cell light attenuation of the hydrogen passivation process, which comprises a DC power supply 1, single crystal cell 2, the conductive plate 3, the vent hole 4, aluminum plate 5; characterized in that the DC power supply 1 through the wire with the single crystal cell 2 on said conductive separator 3 is electrically connected with the; single crystal cell 2 is externally provided with the external temperature control system; said external temperature control system comprises an air hole 4, aluminum plate 5 form; said single crystal cell 2 are on two sides of the aluminum plate with a through hole 5; the above-mentioned aluminum plate 5 are installed on one side of a vent hole 4, the above-mentioned aluminum plate 5 with the through hole of the vent are 4 connected, it is through gas flow meter to adjust the blowing flow and the heating of the cell or maintain the temperature to the temperature of the temperature.

Wherein said hydrogen passivation process is crystal cell 2 surface SiN: H film layer in the H, through the control of the direct current power supply 1 is applied to the single crystal on the battery current, single crystal cell 2 and the temperature of the power-on time, to adjust the silicon in the substrate of the B - O defect in high and low between, at the same time utilize the current to adjust to the same H , thereby achieving the decay rate of the battery; the hydrogen passivation process can also be applied to such single crystal and polycrystalline solar cell, and such single crystal and polycrystalline solar cell to improve the light decay in the process will not reduce the photoelectric conversion efficiency of the battery.

The process of the single crystal cell in the light decay under standard test conditions for the photoelectric conversion efficiency is calculated -0.07% -0.02%, optical attenuation is 0.2% -1.5%.

Embodiment 1:

A method for improving the light decay single crystal solar cell of the hydrogen passivation process, which comprises a DC power supply 1, single crystal cell 2, the conductive plate 3, the vent 4, ventilating plate 5, ; characterized in that the DC power supply 1 through the wire with the single crystal cell 2 on said conductive separator 3 is electrically connected with the; single crystal cell 2 is externally provided with the external temperature control system; said external temperature control system comprises an air hole 4, ventilating plate 5 form; said single crystal cell 2 are on two sides of ventilation with air holes 5; the above ventilation plate 5 are installed on one side of a vent hole 4, the above-mentioned aluminum plate 5 are vent holes 4 connected, it is through gas flow meter to adjust the blowing flow and the heating of the cell or maintain the temperature to the temperature of the temperature.

The hydrogen passivation process is crystal cell 2 surface SiN: H film layer in the H, through the control of the direct current power supply 1 is applied to the single crystal on the battery current, single crystal cell 2 and the temperature of the power-on time, to adjust the silicon in the substrate of the B - O defect in high and low between, at the same time utilize the current to adjust to the same H , thereby achieving the decay rate of the battery; the hydrogen passivation process can also be applied to such single crystal and polycrystalline solar cell, and such single crystal and polycrystalline solar cell to improve the light decay in the process will not reduce the photoelectric conversion efficiency of the battery.

The conductive partition walls 3 and the tooth 5 is the aluminum sheet.

The conductive partition walls 3 and the ventilation plate 5 has a thickness of 5 mm.

A method for improving the light decay single crystal solar cell of the hydrogen passivation process, its referred to in the process system consists in the following: a stacked series of single crystal battery, a direct current power supply, the conductive separator, the external temperature control system, wire.

Wherein said conductive separator is the aluminum sheet;

A method for improving the light decay single crystal solar cell of the hydrogen passivation process, completed by the following steps:

1st stage: the single crystal cell stack connected in series, with the same specification to stack the single crystal cell connected in series, the number of the cell 350 sheet; in battery chip add a block under the aluminum plate, the two ends of its benefits is the protection of the battery electrode sheet from scratch;

2nd stage: a direct current power source are connected to the single crystal cell anode (P-type end), cathode is connected to the negative pole of the battery (N-type end), to the battery applying forward current is applied 3 A; external temperature control system is stable and the battery temperature is 135 °C; maintain 30 min;

3rd stage: after the end of the 2nd stage, the battery applying forward current is applied 10 A; external temperature control system is stable and the battery temperature is 180 °C; maintain 20 min;

4th stage: after the end of the 3rd stage, the battery applying forward current is applied 8 A; external temperature control system is stable and the battery temperature is 175 °C; maintain 50 min through the cooling system to normal temperature after the follow-up process.

Wherein the single crystal cell stack connected in series mode is to adopt the every 8 H-cell stacked in series in the same direction.

The process of bead which it is single crystal cell in standard light decay test conditions the illumination power is 3000 W, test time is 12 hours.

Embodiment 2:

The remaining with the embodiment 1

The conductive partition walls 3 and the tooth 5 is a copper plate.

The conductive partition walls 3 and the ventilation plate 5 has a thickness of 7 mm.

A method for improving the light decay single crystal solar cell of the hydrogen passivation process, completed by the following steps:

1st stage: the single crystal cell stack connected in series, with the same specification to stack the single crystal cell connected in series, the number of the cell 270 sheet; in battery chip add a block under the copper plate, the two ends of its benefits is to protect the battery electrode sheet from scratch;

2nd stage: a direct current power source are connected to the single crystal cell anode (P-type end), cathode is connected to the negative pole of the battery (N-type end), to the battery applying forward current is applied 5 A; external temperature control system is stable and the battery temperature is 130 °C; maintain 25 min;

3rd stage: after the end of the 2nd stage, the battery applying forward current is applied 9 A; external temperature control system is stable and the battery temperature is 185 °C; maintain 15 min;

4th stage: after the end of the 3rd stage, the battery applying forward current is applied 6 A; external temperature control system is stable and the battery temperature is 160 °C; maintain 55 min through the cooling system to normal temperature after the follow-up process.

Wherein the single crystal cell stack connected in series mode is to adopt the each 12 connected in series with the battery to stack the way cross.

The process of bead which it is single crystal cell in standard light decay test conditions the illumination power is 2000 W, test time is 5 hours.

Embodiment 3:

The remaining with the embodiment 1

The conductive partition walls 3 and the ventilation plate 5 for the lead plate.

The conductive partition walls 3 and the ventilation plate 5 has a thickness of 3 mm.

A method for improving the light decay single crystal solar cell of the hydrogen passivation process, completed by the following steps:

1st stage: the single crystal cell stack connected in series, with the same specification to stack the single crystal cell connected in series, the number of the cell 200 sheet; the battery on-chip all add a lead, its benefits is to protect the battery a by the two ends of the electrode scratch;

2nd stage: a direct current power source are connected to the single crystal cell anode (P-type end), cathode is connected to the negative pole of the battery (N-type end), to the battery applying forward current is applied 4 A; external temperature control system is stable and the battery temperature is 140 °C; maintain 20 min;

3rd stage: after the end of the 2nd stage, applying forward current is applied to the battery 11 A; external temperature control system is stable and the battery temperature is 190 °C; maintain 10 min;

4th stage: after the end of the 3rd stage, the battery applying forward current is applied 7 A; external temperature control system is stable and the battery temperature is 170 °C; maintaining the 45 min after passes through the cooling system to the room temperature the follow-up process.

Wherein the single crystal cell stack connected in series mode is to adopt the every 10 to stack the battery connected in series with the H-mode.

The process of bead which it is single crystal cell in standard light decay test conditions the illumination power is 1000 W, test time is 9 hours.

Embodiment 4:

The remaining with the embodiment 1

The conductive partition walls 3 and the ventilation plate 5 for the round saw;

The conductive partition walls 3 and the ventilation plate 5 has a thickness of 4 mm.

A method for improving the light decay single crystal solar cell of the hydrogen passivation process, completed by the following steps:

1st stage: the single crystal cell stack connected in series, with the same specification to stack the single crystal cell connected in series, the number of the cell 360 sheet; in all battery chip add a block of the round saw, its benefits is to protect the battery a by the two ends of the electrode scratch;

2nd stage: a direct current power source are connected to the single crystal cell anode (P-type end), cathode is connected to the negative pole of the battery (N-type end), to the battery applying forward current is applied 2 A; external temperature control system is stable and the battery temperature is 145 °C; maintain 10 min;

3rd stage: after the end of the 2nd stage, the battery applying forward current is applied 7 A; external temperature control system is stable and the battery temperature is 170 °C; maintain 25 min;

4th stage: after the end of the 3rd stage, the battery applying forward current is applied 9 A; external temperature control system is stable and the battery temperature is 180 °C; maintain the 60 min after passes through the cooling system to the room temperature the follow-up process.

Wherein the single crystal cell stack connected in series mode is to adopt the each 9 cell connected in series with the H-type manner to stack.

The process of bead which it is single crystal cell in standard light decay test conditions the illumination power of 2500 W, test time is 7 hours.

Embodiment 5:

The remaining with the embodiment 1

The conductive partition walls 3 and the ventilation plate 5 for the zinc plate.

The conductive partition walls 3 and the ventilation plate 5 has a thickness of 6 mm.

A method for improving the light decay single crystal solar cell of the hydrogen passivation process, completed by the following steps:

1st stage: the single crystal cell stack connected in series, with the same specification to stack the single crystal cell connected in series, the number of the cell 150 sheet; the battery on-chip under various heating a zinc plate, its benefits is to protect the battery a by the two ends of the electrode scratch;

2nd stage: a direct current power source are connected to the single crystal cell anode (P-type end), cathode is connected to the negative pole of the battery (N-type end), to the battery applying forward current is applied 4.5 A; external temperature control system is stable and the battery temperature is 150 °C; maintain 40 min;

3rd stage: after the end of the 2nd stage, the battery applying forward current is applied 12 A; external temperature control system is stable and the battery temperature is 200 °C; maintain 5 min;

4th stage: after the end of the 3rd stage, the battery applying forward current is applied 5 A; external temperature control system is stable and the battery temperature is 140 °C; maintain 30 min through the cooling system to normal temperature after the follow-up process.

Wherein the single crystal cell stack connected in series mode is to adopt the every 10 connected in series with the battery to stack the way cross.

The process of bead which it is single crystal cell in standard light decay test conditions the illumination power is 1500 W, test time is 11 hours.

Embodiment 6:

The remaining with the embodiment 1

A method for improving the light decay single crystal solar cell of the hydrogen passivation process, applied in the single crystal solar cell on the, process is similar to a single cell in the cell are, properties with light decay in table 1.

Embodiment 7:

The remaining with the embodiment 1

A method for improving the light decay single crystal solar cell of the hydrogen passivation process, is applied to the polycrystalline silicon solar battery, process the cell in the cell are polycrystalline silicon, properties with light decay in table 1.

The ratio 1:

The remaining with the embodiment 1

A method for improving the light decay single crystal solar cell of the hydrogen passivation process, completed by the following steps:

1st stage: the single crystal cell stack connected in series, with the same specification to stack the single crystal cell connected in series, the number of the cell 350 sheet; the battery on-chip under various heating a zinc plate, its benefits is to protect the battery a by the two ends of the electrode scratch;

2nd stage: a direct current power source are connected to the single crystal cell anode (P-type end), cathode is connected to the negative pole of the battery (N-type end), to the battery applying forward current is applied 8 A; external temperature control system is stable and the battery temperature is 160 °C; maintain 5 min;

3rd stage: after the end of the 2nd stage, the battery applying forward current is applied 4 A; external temperature control system is stable and the battery temperature is 120 °C; maintain 35 min;

4th stage: after the end of the 3rd stage, the battery applying forward current is applied 12 A; external temperature control system is stable and the battery temperature is 200 °C; maintain 15 min after passes through the cooling system to the room temperature the follow-up process.

Wherein the single crystal cell stack connected in series mode is to adopt the each 5 connected in series with the battery in a manner to stack the cross.

The process of bead which it is single crystal cell in standard light decay test conditions the illumination power is 3500 W, test time is 4 hours.

To the ratio 2:

The remaining with the embodiment 1

A method for improving the light decay single crystal solar cell of the hydrogen passivation process, completed by the following steps:

1st stage: the single crystal cell stack connected in series, with the same specification to stack the single crystal cell connected in series, the number of the cell 70 sheet; the battery on-chip under various heating a zinc plate, its benefits is to protect the battery a by the two ends of the electrode scratch;

2nd stage: a direct current power source are connected to the single crystal cell anode (P-type end), cathode is connected to the negative pole of the battery (N-type end), to the battery applying forward current is applied 0.5 A; external temperature control system is stable and the battery temperature is 60 °C; maintaining the 45 min;

3rd stage: after the end of the 2nd stage, the battery applying forward current is applied 15 A; external temperature control system is stable and the battery temperature is 220 °C; maintain 4 min;

4th stage: after the end of the 3rd stage, the battery applying forward current is applied 4 A; external temperature control system is stable and the battery temperature is 120 °C; maintain 65 min through the cooling system to normal temperature after the follow-up process.

Wherein the single crystal cell stack connected in series mode is to adopt the every 15 to stack the cell connected in series with the H-shaped manner.

The process of bead which it is single crystal cell in standard light decay test conditions the illumination power is 500 W, test time is 14 hours.

Test examples 1 - 7 and to the ratio 1 - 2, all the electrical property and the light attenuation in the table below:

Note: the light fades rate=(light attenuation pre-efficiency - the efficiency of the light decay after) the light decay/front efficiency;

The corresponding efficiency gain estimation according to the galvanic cell efficiency is 20%, the light decay of 2.5% estimate, such as the embodiment 1 in=(20 - 0 .07) * (1 - 0 .0062) -20 * (1 - 0 .025)=0.306.

From the table it can be seen, the scope of the invention embodiments 1, 2, 3, after treatment to reduce the range of efficiency and greatly improve the light of within the range of requirements, and to compare with the ratio is obtained under the high efficiency gain, effectively improve the long-term stability of the photovoltaic cell power generation capacity, the selected process temperature and current is easy to reach and control, can be very good for industrial production, has a relatively high value.