Thermoelectric conversion element and thermoelectric conversion module
View Patent ↗The present invention provides a thermoelectric element in which a thin film of p-type thermoelectric material and a thin film of n-type thermoelectric material, which are formed on an electrically insulating substrate, are electrically connected, in which the p-type thermoelectric material and the n-type thermoelectric material are selected from specific complex oxides with a positive Seebeck coefficient and specific complex oxides with a negative Seebeck coefficient, respectively. The present invention also provides a thermoelectric module using the thermoelectric element(s) and a thermoelectric conversion method. In the thermoelectric element of the present invention, since a p-type thermoelectric material and an n-type thermoelectric material are formed into a thin film on an electrically insulating substrate, the thermoelectric element of the invention can be formed on substrates having various shapes, thereby providing thermoelectric elements having various shapes.
1. A thermoelectric element comprising:
a thin film of p-type thermoelectric material,
a thin film of n-type thermoelectric material, and
the thin film of p-type thermoelectric material and the thin film of n-type thermoelectric material being formed on the electrically insulating substrate and being electrically connected,
(i) the p-type thermoelectric material comprising at least one complex oxide selected from the group consisting of:
complex oxides represented by Formula Bi f Pb g M h 1 CO i M j 2 O k , wherein M 1 is one or more elements selected from the group consisting of Na, K, Li, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Pb, Ca, Sr, Ba, Al, Y, and lanthanoids; M 2 is one or more elements selected from the group consisting of Ti, V, Cr, Mn, Fe, Ni, Cu, Ag, Mo, W, Nb, and Ta; 1.8≦f≦2.20≦g≦0.4; 1.8≦h≦2.2; 1.6≦i≦2.2; 0≦j≦0.5;and 8≦k≦10; and
(ii) the n-type thermoelectric material comprising at least one complex oxide selected from the group consisting of:
complex oxides represented by the Formula Ln x R y 5 Ni p R q′ 6 O r′ , wherein Ln is lanthanoid; R 5 is one or more elements selected from the group consisting of Na, K, Sr, Ca, Bi, and Nd; R 6 is one or more elements selected from the group consisting of Ti, V, Cr, and Cu 0.5≦x≦1.2; 0≦y≦0.5; 0.5≦p≦1.2; 0.01≦q′≦0.5; and 2.8≦r′≦3.2 .
2. The thermoelectric element according to claim 1 , wherein
the p-type thermoelectric material comprises at least one complex oxide selected from the group consisting of complex oxides represented by the formula: Bi f Pb g M h 1 CO 2 O k , wherein M 1 is one or more elements selected from the group consisting of Sr, Ca and Ba; 1.8≦f≦2.2; 0≦g≦0.4; 1.8≦h≦2.2; and 8≦k≦10;
the n-type thermoelectric material comprises at least one complex oxide selected from the group consisting of complex oxides represented by the formula: Ln x R y 5 Ni p R q′ 6 O r′ , wherein Ln is lanthanoid; R 5 is one or more elements selected from the group consisting of Na, K, Sr, Ca, Bi, and Nd; and R 6 is one or more elements selected from the group consisting of Ti, V, Cr, and Cu; 0.5≦x≦1.2; 0≦y≦0.5; 0.5≦p≦1.2; 0.01≦q′≦0.5; and 2.8≦r′≦3.2.
3. The thermoelectric element according to claim 1 , wherein the thin film of p-type thermoelectric material and the thin film of n-type thermoelectric material are electrically connected by one of the following methods:
bringing one end portion of the thin film of p-type thermoelectric material into direct contact with one end portion of the thin film of n-type thermoelectric material;
bringing one end portion of the thin film of p-type thermoelectric material into contact with one end portion of the thin film of n-type thermoelectric material via an electrically conductive material;
bringing one end portion of the thin film of p-type thermoelectric material into direct contact with one end portion of the thin film of n-type thermoelectric material and covering the contact portion with an electrically conductive material.
4. The thermoelectric element according to claim 1 , wherein the thin film of p-type thermoelectric material and the thin film of n-type thermoelectric material are formed on the same surface or on different surfaces of the electrically insulating substrate.
5. The thermoelectric element according to claim 1 , wherein the electrically insulating substrate is a substrate comprising a plastic material.
6. The thermoelectric element according to claim 1 , wherein thermoelectromotive force is at least 60 μV/K in a temperature range of 293 K to 1073K.
7. The thermoelectric element according to claim 1 , wherein electrical resistance is 1 KΩ or lower in a temperature range of 293 K to 1073 K.
8. A thermoelectric module comprising a plurality of the thermoelectric elements of claim 1 , wherein the thermoelectric elements are electrically connected in series such that an unconnected end portion of a p-type thermoelectric material of one thermoelectric element is electrically connected to an unconnected end portion of an n-type thermoelectric material of another thermoelectric element.
9. A thermoelectric conversion method comprising positioning one end of the thermoelectric module of claim 8 at a high-temperature portion and positioning the other end of the module at a low-temperature portion.