鋁殼和膠蓋密封形成電解。與其他類型的電容器相比，鋁電解電容器在結構上具有以下明顯特點:

(1)鋁(lv)(lv)電(dian)(dian)解電(dian)(dian)容器的(de)工作(zuo)介(jie)質(zhi)是通過陽(yang)極(ji)氧化在鋁(lv)(lv)箔表面形成一層極(ji)薄的(de)三氧化二鋁(lv)(lv)(Al2O3)。這種氧化介(jie)質(zhi)層與(yu)電(dian)(dian)容器的(de)陽(yang)極(ji)結(jie)合成一個完整(zheng)的(de)系統，兩(liang)者相(xiang)(xiang)互依存，不能獨立(li)；我們(men)通常(chang)稱之(zhi)為電(dian)(dian)容器，它們(men)的(de)電(dian)(dian)極(ji)和電(dian)(dian)介(jie)質(zhi)是相(xiang)(xiang)互獨立(li)的(de)。

(2)鋁(lv)電(dian)解電(dian)容器(qi)的(de)陽極是表面生成Al2O3介質層的(de)鋁(lv)箔(bo)。陰(yin)極不(bu)是我們習慣認為的(de)負箔(bo)，而是電(dian)容器(qi)的(de)電(dian)解液(ye)。

(3)負(fu)箔在電(dian)(dian)(dian)(dian)解電(dian)(dian)(dian)(dian)容器(qi)(qi)中起電(dian)(dian)(dian)(dian)引出的作用，因為(wei)電(dian)(dian)(dian)(dian)解液作為(wei)電(dian)(dian)(dian)(dian)解電(dian)(dian)(dian)(dian)容器(qi)(qi)的陰極(ji)(ji)，不能直接(jie)與外電(dian)(dian)(dian)(dian)路連接(jie)，必須通(tong)過另一個(ge)金屬電(dian)(dian)(dian)(dian)極(ji)(ji)和電(dian)(dian)(dian)(dian)路的其(qi)他部(bu)分形成電(dian)(dian)(dian)(dian)路。

(4)鋁(lv)(lv)電解(jie)電容器的陽(yang)極鋁(lv)(lv)箔和陰極鋁(lv)(lv)箔通(tong)常(chang)是腐蝕(shi)性鋁(lv)(lv)箔，實際(ji)表(biao)面(mian)積遠大于其(qi)表(biao)觀表(biao)面(mian)積，這也是鋁(lv)(lv)電解(jie)電容器通(tong)常(chang)電容量大的原因之一(yi)。由于使用了許多細(xi)腐蝕(shi)孔的鋁(lv)(lv)箔，通(tong)常(chang)需(xu)要(yao)液體(ti)電解(jie)質來更有效地利(li)用其(qi)實際(ji)電極面(mian)積。

(5)由于鋁電(dian)(dian)解電(dian)(dian)容(rong)器的介(jie)質氧(yang)化(hua)(hua)膜是通過陽極氧(yang)化(hua)(hua)獲得的，其厚(hou)度與陽極氧(yang)化(hua)(hua)施加(jia)的電(dian)(dian)壓成正比，鋁電(dian)(dian)解電(dian)(dian)容(rong)器的介(jie)質層厚(hou)度原理上可以(yi)人工精確(que)控制(zhi)。