溫差電池中若僅進行
的反應，則其電池電壓與溫差成正比，且純粹是利用化學反應將熱能轉換成電能，我們稱之為「典型溫差電池」，由熱力學公式可推導出典型溫差電池的電動勢(ΔS = S(s)—S(aq)，S為絕對熵， n為得失電子數，1F
= 96487 C )，且得到下列三項推論來說明溫差電池的特殊現象。 (1) 同一溫差電池，其電動勢與溫差成正比 (ε∝ ΔT)。(2)
不同的溫差電池，當溫差一定時，電壓ε 與ΔS 成正比，與得失電子數n 成反比。典型溫差電池中，電解液濃度越小，金屬離子濃度也愈小，會使得ΔS = (S(s)—S(aq))的絕對值變大，因此溫差電池的電壓也就愈大。(3)
ΔS 值的正負決定電壓ε 的正負。Cu(NO3)2 及ZnSO4 溫差電池的ΔS 為正值，所以高溫杯為正極；AgNO3
溫差電池的ΔS 為負值，所以高溫杯為負極。因水溶液中陰、陽離子不能單獨存在，所以單一離子水溶液的絕對熵無法求得，但科學家把氫離子水溶液的標準絕對熵定為零，藉以求出其它離子的絕對熵，然而我們測得在一定溫差時典型溫差電池的電動勢ε，再查得金屬的標準絕對熵
S(s)，代入S(aq) = S(s) — nFε/ΔT，便可得到離子水溶液的絕對熵。Cu(NO3)2
溫差電池的電解液中若含有1M 或0.5M 的KNO3，電池電壓仍然與溫差成正比， 但卻可獲得較大的電流，我們稱此類溫差電池為「改良型溫差電池」。我們利用改良型溫差電池的原理，自製環保、節約能源、可重複使用的實用溫差電池，以PVC
水管當容器，上、下兩端開口用銅片封住當電極，管內裝海棉及0.125M Cu(NO3)與 1M KNO3 溶液，熱源加熱上層銅片形成溫差，當溫差維持在70℃，電壓約為70
mV，若串聯30 個實用溫差電池，電壓可達2 V 以上，就可以對鉛蓄電池充電。實用溫差電池的熱源可由回收冷氣機、工廠的廢熱，或直接利用太陽能來當熱源。
If the temperature difference cell only goes through the following reaction
Then the potential created by the cell is proportional to the temperature difference,
and such a reaction purely changes the thermal energy into electrical energy through
chemical reaction, which we often name it “typical temperature difference cells”.
We can come to the following formula for the typical temperature difference cells
through a series of thermodynamic formula: ε= ΔT ． ΔS/ nF (ΔS = S(s)—S(aq),
where S is the standard 3 entropy, and n is the number of electrons gained or lost,
and 1F = 96487 C). We also provide the following three inferences to demonstrate
the special phenomenon for the temperature difference cells: 1. Within the same
temperature cell, the electromotive force (EMF) is proportional to the temperature
difference. 2. When the temperature difference keeps constant, the electromotive
force is proportional to the ΔS in different temperature cells, and is inversely
proportional to the number of electrons gained or lost. Within the typical temperature
difference cells, when the concentration of the electrolyte becomes more diluted,
the concentration of the metal ions also proportionally become lower, which will
make the absolute value of the following equation bigger, as a result, will make
the electric potential of the temperature difference cells bigger: ΔS = (S(s)—S(aq))
3. The value of ΔS decides the value of the electromotive force. The ΔS of the following
temperature difference cells is positive value: Cu(NO3)2 and
ZnSO4 . As a result, within the copper and zinc temperature difference cells, the
higher temperature glass is the anode. On the other hand, the ΔS of the AgNO3 temperature
difference cell is negative, which means that within the silver temperature difference
cell, the higher temperature glass is the cathode. Meanwhile, because the cations and anions can not exist alone, therefore,
it is not possible to find the standard entropy of the single ion solution. However,
scientists define the standard entropy of the solution containing hydrogen ion to
be zero, as a result, we only have to determine the electromotive force for a typical
temperature difference cell, while keeping the temperature difference constant,
followed by finding the standard entropy for the said metal S(s). Inserting
it into the following equation to find the standard entropy for the ion solution.
S(aq) = S(s) — nFε/ΔT If the electrolytes for the Cu(NO3)2
temperature difference cell contains 1M or 0.5M KNO3 , the electromotive
force is still proportional to the temperature difference, and we can obtain bigger
electric current. We call this kind of temperature difference cells “improved version
of the typical temperature difference cells”. We try to make more environmental,
energy saving, and recyclable temperature difference cell by applying the theory
of the improved version of the typical temperature difference cells. We use PVC
water pipe as the containers, both edges of the pipe sealed with copper metals,
also work as the electrodes. Within the pipe filled with sponge and 0.125M Cu(NO3)
and 1M KNO3 solution. The heat source keeps heating the upper copper metal to keep
constant temperature difference. When the temperature difference is kept around
70℃, the electric potential is 70 mV. If we can connect 30 practical temperature
difference cells in a series, the electric potential will reach 2V, which can then
charge the lead rechargeable battery. The heat sources of the practical temperature
difference cells can be supplied by the recycled air conditioners, heat waste from
a factory, or directly comes from the solar power.
「為配合國家發展委員會「推動ODF-CNS15251為政府為文件標準格式實施計畫」，以及
提供使用者有文書軟體選擇的權利，本館檔案下載部分文件將公布ODF開放文件格式，
免費開源軟體可至LibreOffice下載安裝使用，或依貴慣用的軟體開啟文件。」