超级电容是容量在法拉级体积却很小的电容,现在已经广泛应用在好多电器里面的说...
比如说涅,有些电器用它来作为断电后维持内部时钟运行的暂时性电源,,,
有些容量灰常大的,甚至被当做后备电源来使用...
想起来,我的元件库里有不少的说~
这东西给我的印象就是...首先,容量很大...别的电容用μF,nF,甚至pF(p为10的-12次方)做单位,这种家伙都是上F的!汗一个;其次耐压好低,我手头上这些都2.5V的到6.3V的,再汗一个,现在应该很过时了~
其实,接触过元件的人应该知道,同样体积的电容,容量标的越高,其耐压就越低.反之电压标到很高的,容量就很小...呵呵,灰常简单啦,高中物理都教过C=Q/U啦!假设在某一技术水平下,某一体积的电容器能够储存的电荷量为定值Q,由于式中C跟U成反比,那么标的"容量"(也就是C)越大,那U就越小咯,反之同理。所以决定电容体积大小的应该是电荷量Q啦~
废话一堆了,转入正题。今天上网看到一篇关于"自制超级电容"的文章,老外写的,有意思~
有空可以试试,,,
How It Works
To make C1, Ollie first cut four 2-inch squares of paper towel and five 1.75-inch squares of activated carbon aquarium filter material. He stacked the paper and activated carbon filter squares as shown in Fig. 2. He then placed the two PC boards as shown in Fig. 2 (copper sides facing toward one another) to form a sandwich-like structure that he held together with a rubber band. After the assembly was ready, he dripped some lemon juice into the four sides of the sandwich.
Figure 2. How the homemade super capacitor is assembled.
Ollie's super capacitor demonstration circuit is shown in Fig. 3. In operation, C1 is charged by switching S1 to position 1 for a minute. This will charge C1 to about 3.3 volts. When S1 is switched to position 2, the LED will glow for 15 seconds or more. C1 can then be recharged for another cycle.
其实我没说过我看的懂哈...
结构(看第一张图)就是最上面和最下面各有一块边长1-2寸的覆铜板（做印刷电路板用的那种原料,话说用铜板当然也是很OK的啦），铜箔朝里，中间是几层活性炭(用于'汽车除味'的东东里面就有,貌似鱼缸店里也有的卖)和餐巾纸交错叠加起来，最后在餐巾纸上滴上柠檬汁(LEMON JUICE!话说柠檬有点贵呢)，超级电容就做成了。电路中(第二张图)用6V电池充电后存的电能可以点亮LED(发光二极管)15秒钟或者更长时间(当然,中间串联了一个680Ω的电阻用于限流)。个人觉得那个1kΩ的可以换成小一些的,从原文中可知C1 is charged by switching S1 to position 1 for a minute. This will charge C1 to about 3.3 volts.无非就是限制电容器充电的电流和电压...假如直接使用3.3volts的电源给它充,这个电阻可以直接去掉咯~
好像最近跟电容比较有来往啊...