電動自行車，是指以蓄電池作為輔助能源在普通自行車的基礎上，安裝了電機、控制器、蓄電池、轉把閘把等操縱部件和顯示儀表系統的機電一體化的個人交通工具。 
       電(dian)(dian)(dian)動(dong)自(zi)行(xing)(xing)車(che)(che)(che)，是指(zhi)以蓄(xu)電(dian)(dian)(dian)池(chi)作為輔助(zhu)(zhu)能(neng)源，具(ju)(ju)有兩個(ge)車(che)(che)(che)輪，能(neng)實(shi)現人力(li)騎(qi)行(xing)(xing)、電(dian)(dian)(dian)動(dong)或電(dian)(dian)(dian)助(zhu)(zhu)動(dong)功能(neng)的(de)(de)(de)特(te)(te)種自(zi)行(xing)(xing)車(che)(che)(che)。根據國(guo)家標準對設計最高時速、空(kong)車(che)(che)(che)質量、外(wai)形尺寸的(de)(de)(de)相關(guan)規定，電(dian)(dian)(dian)動(dong)自(zi)行(xing)(xing)車(che)(che)(che)歸屬(shu)非(fei)機(ji)動(dong)車(che)(che)(che)管理范疇，應同時具(ju)(ju)備以下5個(ge)特(te)(te)征(zheng)：必須(xu)具(ju)(ju)備腳踏行(xing)(xing)駛(shi)功能(neng)，蓄(xu)電(dian)(dian)(dian)池(chi)只作為輔助(zhu)(zhu)能(neng)源；必須(xu)具(ju)(ju)備兩個(ge)車(che)(che)(che)輪；設計車(che)(che)(che)速不(bu)(bu)大于20公里/小時；整車(che)(che)(che)重量不(bu)(bu)大于40公斤；輪胎寬(kuan)度（胎內）不(bu)(bu)大于54毫米(mi)。 　　電(dian)(dian)(dian)動(dong)自(zi)行(xing)(xing)車(che)(che)(che)的(de)(de)(de)型(xing)號以TD（特(te)(te)種自(zi)行(xing)(xing)車(che)(che)(che)種類(lei)的(de)(de)(de)電(dian)(dian)(dian)動(dong)自(zi)行(xing)(xing)車(che)(che)(che)類(lei)）冠(guan)號。它雖(sui)然具(ju)(ju)有普通自(zi)行(xing)(xing)車(che)(che)(che)的(de)(de)(de)外(wai)表特(te)(te)征(zheng)（甚至具(ju)(ju)有摩托(tuo)車(che)(che)(che)的(de)(de)(de)外(wai)表特(te)(te)征(zheng)），但是主(zhu)要的(de)(de)(de)是，它是在普通自(zi)行(xing)(xing)車(che)(che)(che)的(de)(de)(de)基礎上，安裝了電(dian)(dian)(dian)機(ji)、控(kong)制器、蓄(xu)電(dian)(dian)(dian)池(chi)、轉把(ba)閘把(ba)等操縱部件和顯(xian)示儀表系統的(de)(de)(de)機(ji)電(dian)(dian)(dian)一(yi)體化的(de)(de)(de)個(ge)人交通工具(ju)(ju)。

主要部件
充電器
　　充電器是給電池補充電能的裝置，一般分二階段充電模式與三階段模式兩種。二階段充電模式：先恒壓充電，充電電流隨電池電壓的上升逐漸減 　　  美國恩達鋰電動車(圖2)
小(xiao)，等電(dian)(dian)(dian)(dian)池(chi)(chi)電(dian)(dian)(dian)(dian)量補充(chong)(chong)(chong)到(dao)一(yi)定(ding)(ding)程度以后，電(dian)(dian)(dian)(dian)池(chi)(chi)電(dian)(dian)(dian)(dian)壓會上(shang)升到(dao)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)器的設(she)定(ding)(ding)值，此時(shi)轉換問涓流(liu)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)。三階段充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)模(mo)式：充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)開始時(shi)，先恒流(liu)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)，迅速(su)給(gei)(gei)電(dian)(dian)(dian)(dian)池(chi)(chi)補充(chong)(chong)(chong)能量；等電(dian)(dian)(dian)(dian)池(chi)(chi)電(dian)(dian)(dian)(dian)壓上(shang)升后轉為(wei)恒壓充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)，此時(shi)電(dian)(dian)(dian)(dian)池(chi)(chi)能量緩慢補充(chong)(chong)(chong)，電(dian)(dian)(dian)(dian)池(chi)(chi)電(dian)(dian)(dian)(dian)壓繼續上(shang)升；達到(dao)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)器的充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)終止電(dian)(dian)(dian)(dian)壓值時(shi)，轉為(wei)涓流(liu)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)，以保養電(dian)(dian)(dian)(dian)池(chi)(chi)和供給(gei)(gei)電(dian)(dian)(dian)(dian)池(chi)(chi)的自放電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)流(liu)。 

電池
　　電(dian)(dian)(dian)(dian)池(chi)(chi)是(shi)提供電(dian)(dian)(dian)(dian)動(dong)(dong)(dong)車(che)(che)(che)能量的(de)(de)隨車(che)(che)(che)能源，目前電(dian)(dian)(dian)(dian)動(dong)(dong)(dong)車(che)(che)(che)主(zhu)(zhu)要采用鉛(qian)酸(suan)電(dian)(dian)(dian)(dian)池(chi)(chi)組(zu)合。另(ling)外鎳氫電(dian)(dian)(dian)(dian)池(chi)(chi)與鋰離子電(dian)(dian)(dian)(dian)池(chi)(chi)也已在一(yi)些輕便折疊電(dian)(dian)(dian)(dian)動(dong)(dong)(dong)車(che)(che)(che)上(shang)開始(shi)使(shi)用了。 　　使(shi)用提示：控制器主(zhu)(zhu)控板(ban)為電(dian)(dian)(dian)(dian)動(dong)(dong)(dong)車(che)(che)(che)主(zhu)(zhu)回路(lu)，具有較(jiao)大工作(zuo)電(dian)(dian)(dian)(dian)流，會發出較(jiao)大熱量。因此(ci)，電(dian)(dian)(dian)(dian)動(dong)(dong)(dong)車(che)(che)(che)不(bu)要停放在陽光下曝曬(shai)，也不(bu)要長時間淋雨，以免控制器出故障。 　　1、低于市(shi)(shi)場(chang)(chang)平(ping)均批(pi)發價(jia)的(de)(de)電(dian)(dian)(dian)(dian)池(chi)(chi)堅(jian)決(jue)(jue)(jue)不(bu)買。 　　2、沒經過2年以上(shang)的(de)(de)市(shi)(shi)場(chang)(chang)考驗的(de)(de)產品。 　　3、沒有電(dian)(dian)(dian)(dian)動(dong)(dong)(dong)車(che)(che)(che)廠家配車(che)(che)(che)的(de)(de)電(dian)(dian)(dian)(dian)池(chi)(chi)堅(jian)決(jue)(jue)(jue)不(bu)買。 　　4、高價(jia)電(dian)(dian)(dian)(dian)池(chi)(chi)，如果不(bu)是(shi)大廠生產的(de)(de)，堅(jian)決(jue)(jue)(jue)不(bu)買。 　　5、改變(bian)國(guo)家標準尺(chi)寸的(de)(de)電(dian)(dian)(dian)(dian)池(chi)(chi)堅(jian)決(jue)(jue)(jue)不(bu)賣(mai)。 　　6、5A放電(dian)(dian)(dian)(dian)，30秒時電(dian)(dian)(dian)(dian)壓高于12.68V的(de)(de)堅(jian)決(jue)(jue)(jue)不(bu)賣(mai)，90%以上(shang)是(shi)短命(ming)電(dian)(dian)(dian)(dian)池(chi)(chi)。 　　檢測(ce)電(dian)(dian)(dian)(dian)池(chi)(chi)的(de)(de)最(zui)簡單方(fang)法：5A放電(dian)(dian)(dian)(dian)，30秒時電(dian)(dian)(dian)(dian)壓低于12.63，前3分種電(dian)(dian)(dian)(dian)壓不(bu)降(jiang)反(fan)升，反(fan)升越多，質量越好(hao)。

控制器
　　  電動自行車(圖1)
控制器是控制電機轉速的部件，也是電動車電氣系統的核心，具有欠壓、限流或過流保護功能。智能型控制器還具有多種騎行模式和整車電氣部件自檢功能。控制器是電動車能量管理與各種控制信號處理的核心部件。
轉把、閘把、助力傳感器
　　轉把、閘把、助力傳感器等是控制器的信號輸入部件。轉把信號是電動車剎車速度信號。閘把信號是當電動車剎車時，閘把內部電子電路輸出給控制器的一個電信號；控制器接收到這個信號后，就會切斷對電機的供電，從而實現剎車斷電功能。助力傳感器是當電動車處于助力狀態是檢測騎行腳蹬力回腳蹬速度信號的裝置。控制器根據電驅動功率，以達到人力與電力自動匹配，共同驅動電動車旋轉。
電機
　　  電動自行車(圖2)
電動自行車最重要的配件是電機，一輛電動自行車的電機基本決定了這輛車的性能和檔次。目前電動自行車所使用的電機大都是高效稀土永磁電機，其中主要又分高速有刷＋齒輪減速電機、低速有刷電機和低速無刷電機三種，目前以高速有刷＋齒輪減速電機性能最好，價格也貴；低速有刷電機要便宜一些，但性能要差一些；無刷電機由于對控制器質量要求極高，上市的品牌不多，普通消費者購買時最好挑選品牌。 　　(美國恩達鋰電動自行車)提供我們知道，電動自行車electric bicycle（以下簡稱電動車）是以蓄電池、鋰電池等電能作為輔助能源，具有兩個車輪，能實現人力騎行、電動或電助動功能的特種自行車。 　　電機是將電池電能轉換機械能，驅動電動車輪旋轉的部件。在電動車上使用的電機，其機械結構、轉速范圍與通電形式上有許多種。常見的有：有刷有齒輪轂電機、有刷無齒輪轂電機、無刷無齒輪轂電機、無刷有齒輪轂電機、高磁盤電機、側掛電機等。 　　使用提示：充電時。保持充電器通風良好。如果在充電過程聞到異味或充電器外殼溫度過高，請立即停止充電，檢查，處理。
燈具、儀表
　　燈具(ju)、儀表部(bu)(bu)分是提供照明并(bing)顯(xian)示電(dian)動車(che)狀態(tai)(tai)(tai)的部(bu)(bu)件組(zu)合。儀表一般(ban)提供電(dian)池(chi)電(dian)壓顯(xian)示、整(zheng)(zheng)車(che)速度顯(xian)示、騎行(xing)狀態(tai)(tai)(tai)顯(xian)示、燈具(ju)狀態(tai)(tai)(tai)顯(xian)示等。智能型儀表還能顯(xian)示整(zheng)(zheng)車(che)各電(dian)氣(qi)部(bu)(bu)件的故障(zhang)情(qing)況(kuang)。