消費(fei)電子產品以及許多(duo)其他行(xing)業都(dou)越來越講究產品的(de)(de)(de)移動(dong)性(xing)(xing)，醫(yi)療(liao)器(qi)械制造商(shang)也不例(li)外，這樣的(de)(de)(de)趨勢提高了(le)現場救助設備、監(jian)控(kong)設備和(he)固定醫(yi)療(liao)設備的(de)(de)(de)性(xing)(xing)能(neng)，進而(er)推動(dong)了(le)醫(yi)療(liao)保健行(xing)業的(de)(de)(de)發展。不過除了(le)便攜性(xing)(xing)以外，醫(yi)療(liao)器(qi)械制造商(shang)當然還希望能(neng)夠制造出可(ke)靠性(xing)(xing)高的(de)(de)(de)器(qi)械，因為人(ren)們(men)的(de)(de)(de)生命往(wang)往(wang)命懸(xuan)一線。手機(ji)壞了(le)固然是惱(nao)人(ren)的(de)(de)(de)事，但(dan)如(ru)果便攜式(shi)心臟監(jian)控(kong)儀(yi)或者輸(shu)液泵由于電池耗盡而(er)停止(zhi)運作，終端(duan)用戶(hu)――及病人(ren)――面(mian)臨的(de)(de)(de)問題(ti)則嚴重(zhong)得多(duo)。 一種能(neng)量(liang)密度(du)更高的(de)(de)(de)技術可(ke)以釋(shi)放比其它同類產品更多(duo)的(de)(de)(de)能(neng)量(liang)，且體(ti)積更小。

    幾年前，醫療專業人員還無法將救助生命的設備帶到現場；因為那時便攜式儀器的技術尚未成熟。但如今，大量的監控儀器、超聲設備和輸液泵可在遠離醫院的場所使用――甚至戰場。便攜式設備的移動越來越方便。正是由于諸如鋰離子電池等技術(shu)的(de)應用(yong)，重達50磅的(de)笨(ben)重除(chu)顫器才可(ke)以被(bei)更(geng)輕(qing)便(bian)、更(geng)緊湊的(de)用(yong)戶(hu)友好型裝置取代(dai)，也不(bu)會(hui)造成醫護人員(yuan)肌肉(rou)的(de)拉傷。

    病(bing)人的移(yi)動性也變得(de)越(yue)來越(yue)重要。如今的病(bing)人可(ke)能會從(cong)放(fang)射科轉(zhuan)移(yi)到重癥監護(hu)病(bing)房，從(cong)救護(hu)車轉(zhuan)移(yi)到急救室，或用救護(hu)車從(cong)一家醫(yi)院(yuan)轉(zhuan)移(yi)到另一家醫(yi)院(yuan)。同樣(yang)地，便(bian)攜式家用儀器(qi)和移(yi)動式監控設備的普及(ji)，使病(bing)人可(ke)以待在喜歡的地方，而并不(bu)一定要留(liu)在醫(yi)療機構中。便(bian)攜式醫(yi)療器(qi)械必須(xu)真正實現(xian)完全意義上的便(bian)攜，為病(bing)人提供最佳服務。

    對(dui)更小型、更輕便的(de)醫(yi)療器(qi)械的(de)需求也(ye)因此顯著(zhu)增加，這大(da)大(da)激發了(le)人們對(dui)更高(gao)能量(liang)密度、更小巧的(de)電池(chi)組的(de)興趣。筆記(ji)本電腦和(he)手機使(shi)用(yong)的(de)鋰離子電池(chi)技術已經有了(le)許(xu)多突(tu)破，醫(yi)療設備設計(ji)工程師可以(yi)對(dui)此加以(yi)創新利(li)用(yong)。

    與其它傳(chuan)統技術相比(bi)，鋰離子(zi)電(dian)池在(zai)便(bian)攜(xie)式醫療設備的應用(yong)中(zhong)具有很多優勢。這包括能量密(mi)度(du)更(geng)(geng)高、重量更(geng)(geng)輕、循環壽命更(geng)(geng)長、電(dian)池容量保(bao)持特性更(geng)(geng)好，以及適用(yong)溫度(du)范圍更(geng)(geng)廣。

    由于化學(xue)性(xing)(xing)質獨(du)特(te)，鋰離(li)子技(ji)術對設計方(fang)面的(de)限制與先(xian)前的(de)電池技(ji)術如鎳(nie)氫化合物(NiMH)、鎳(nie)鎘(NiCd)和密封(feng)鉛酸(SLA)不同(tong)。同(tong)時，醫療設備在某些方(fang)面比消費電子產品(pin)有更嚴格的(de)操作(zuo)要(yao)求；由于可靠性(xing)(xing)非常(chang)重(zhong)要(yao)，因此需要(yao)有功能(neng)強大的(de)電池組，帶有精確電量(liang)監測且(qie)可靠的(de)電池。

    本文結(jie)合醫療器械(xie)的要求(qiu)及鋰(li)離(li)子技(ji)術的特性(xing)，概述(shu)了便攜(xie)式(shi)電源系統設計的注意事項。并比較了鋰(li)離(li)子電池和其它(ta)化(hua)學(xue)電池的特性(xing)和容量。

    能量密度和電壓

    鋰離子電池技術的主要優勢在于其能量密度的顯著提高。相同體積和重量時，鋰離子電池可儲存和(he)釋放的(de)能(neng)量(liang)比(bi)其它充電(dian)(dian)電(dian)(dian)池更高。能(neng)量(liang)密(mi)度(du)以體(ti)積和(he)質(zhi)量(liang)兩種(zhong)方式測量(liang)。鋰離子技術現可以提供近500Wh/L的(de)體(ti)積能(neng)量(liang)密(mi)度(du)和(he)200Wh/kg的(de)質(zhi)量(liang)能(neng)量(liang)密(mi)度(du)(見圖1)。

    圖1.鋰離(li)子的能量密度遠高(gao)于鎳化合(he)物。

    與其(qi)它技術(shu)相比，鋰離(li)子(zi)可(ke)(ke)以釋(shi)放更(geng)多的能(neng)量，而(er)且體(ti)積(ji)更(geng)小，質量更(geng)輕。鋰離(li)子(zi)電池(chi)(chi)的工作電壓比其(qi)它充電電池(chi)(chi)更(geng)高，通常約為(wei)3.7V，而(er)NiCd或NiMH電池(chi)(chi)為(wei)1.2V。這意(yi)味著需要(yao)使(shi)用(yong)多節(jie)其(qi)它電池(chi)(chi)時，僅需一節(jie)鋰離(li)子(zi)電池(chi)(chi)即可(ke)(ke)滿足(zu)使(shi)用(yong)要(yao)求。便攜式儀器(qi)設(she)計中使(shi)用(yong)的電池(chi)(chi)能(neng)量密度越(yue)高，其(qi)產品的體(ti)積(ji)越(yue)小，便攜性也(ye)越(yue)好(hao)。

    電(dian)池組(zu)體積的縮小表示工程師可以利用多余空間，在同一產品中(zhong)增添更多新功能(見圖2)。

    圖2.鋰離(li)子電池(chi)(chi)有圓(yuan)柱(zhu)形(xing)和(he)棱柱(zhu)形(xing)兩種形(xing)狀，可制成不同(tong)尺寸和(he)容量的電池(chi)(chi)。

    自放電

    充(chong)電電池的容(rong)量會不(bu)斷損失。該現象即稱(cheng)為自放電。但若儲存得當，其損失的大(da)部(bu)分容(rong)量仍可恢復(fu)。

    所有電(dian)(dian)(dian)池(chi)(chi)均應在(zai)室溫(wen)（25°C或(huo)更低）下儲(chu)存，以保持最大的(de)(de)電(dian)(dian)(dian)池(chi)(chi)容(rong)量(liang)(liang)。終端用戶須將(jiang)SLA電(dian)(dian)(dian)池(chi)(chi)放(fang)(fang)(fang)在(zai)低溫(wen)下儲(chu)存，并盡(jin)可(ke)能每次充電(dian)(dian)(dian)量(liang)(liang)接近其容(rong)量(liang)(liang)的(de)(de)100%，以保持最佳性能。密封鉛電(dian)(dian)(dian)池(chi)(chi)在(zai)25°C下放(fang)(fang)(fang)置6個月后(hou)自(zi)(zi)放(fang)(fang)(fang)電(dian)(dian)(dian)容(rong)量(liang)(liang)約(yue)為(wei)20%；但40°C放(fang)(fang)(fang)置6個月后(hou)該值(zhi)則增加(jia)到約(yue)30%。NiMH電(dian)(dian)(dian)池(chi)(chi)也(ye)應遵循類似的(de)(de)建議(yi)，避(bi)免長期儲(chu)存使反應物失活。NiCd和NiMH電(dian)(dian)(dian)池(chi)(chi)在(zai)25°C下放(fang)(fang)(fang)置1個月，其自(zi)(zi)放(fang)(fang)(fang)電(dian)(dian)(dian)率約(yue)為(wei)20%，隨后(hou)自(zi)(zi)放(fang)(fang)(fang)電(dian)(dian)(dian)率的(de)(de)增速(su)顯著(zhu)減慢。相反，當鋰(li)離子電(dian)(dian)(dian)池(chi)(chi)儲(chu)存時(shi)的(de)(de)充電(dian)(dian)(dian)電(dian)(dian)(dian)量(liang)(liang)為(wei)30-50%時(shi)，可(ke)獲得最佳循環壽(shou)命。鋰(li)離子電(dian)(dian)(dian)池(chi)(chi)25°C儲(chu)存6個月后(hou)的(de)(de)自(zi)(zi)放(fang)(fang)(fang)電(dian)(dian)(dian)容(rong)量(liang)(liang)僅為(wei)10%。

    倍(bei)率(lv)特性

    選(xuan)擇材料(liao)時，應(ying)考慮到(dao)其(qi)終端裝置(zhi)(zhi)的涌流和最大放(fang)電(dian)率。電(dian)池或電(dian)池組以高倍率放(fang)電(dian)會造成電(dian)壓下降。如果設(she)計時沒有考慮到(dao)這方(fang)面，終端裝置(zhi)(zhi)可能會由(you)于電(dian)壓不足(zu)而關閉(bi)。

    高(gao)倍(bei)(bei)率(lv)的(de)NiCd電(dian)(dian)(dian)池的(de)連(lian)續放(fang)電(dian)(dian)(dian)率(lv)可(ke)達(da)2C（電(dian)(dian)(dian)池額定容(rong)量(liang)的(de)兩(liang)倍(bei)(bei)）甚(shen)至(zhi)更高(gao)，具體取(qu)決于(yu)電(dian)(dian)(dian)池原料及(ji)內部阻抗。許(xu)多SLA電(dian)(dian)(dian)池的(de)連(lian)續放(fang)電(dian)(dian)(dian)率(lv)可(ke)達(da)3C甚(shen)至(zhi)更高(gao)。大(da)部分的(de)鋰離(li)子(zi)電(dian)(dian)(dian)池的(de)連(lian)續放(fang)電(dian)(dian)(dian)率(lv)僅為1C，但采用該技術的(de)新電(dian)(dian)(dian)池，其(qi)連(lian)續放(fang)電(dian)(dian)(dian)率(lv)極高(gao)，達(da)到80A，可(ke)持續30秒，在與NiCd和(he)SLA電(dian)(dian)(dian)池的(de)競爭(zheng)中具有很(hen)大(da)的(de)優勢。

    循(xun)環(huan)壽命

    電(dian)(dian)(dian)池(chi)(chi)的(de)(de)循環(huan)壽命是電(dian)(dian)(dian)池(chi)(chi)容量(liang)下(xia)降到(dao)其原始容量(liang)的(de)(de)某一規定(ding)百(bai)分比之前，電(dian)(dian)(dian)池(chi)(chi)所經歷的(de)(de)充(chong)放電(dian)(dian)(dian)循環(huan)次(ci)數。鉛酸電(dian)(dian)(dian)池(chi)(chi)的(de)(de)循環(huan)壽命約為250至(zhi)500次(ci)，具(ju)體(ti)取決于制造商(shang)的(de)(de)產品(pin)質量(liang)和(he)放電(dian)(dian)(dian)深(shen)度(du)（放電(dian)(dian)(dian)容量(liang)最多至(zhi)額(e)定(ding)容量(liang)的(de)(de)60%）。NiCd、NiMH和(he)鋰離(li)子電(dian)(dian)(dian)池(chi)(chi)通(tong)常可(ke)耐受500-700次(ci)充(chong)放電(dian)(dian)(dian)循環(huan)，其容量(liang)僅下(xia)降為額(e)定(ding)容量(liang)的(de)(de)80%。不管使(shi)(shi)用何種化學物質，電(dian)(dian)(dian)池(chi)(chi)放電(dian)(dian)(dian)深(shen)度(du)越(yue)深(shen)，用戶可(ke)使(shi)(shi)用的(de)(de)循環(huan)次(ci)數就越(yue)少(shao)。

    充電差異

    鋰離(li)子(zi)電(dian)(dian)(dian)(dian)池(chi)的(de)充(chong)(chong)電(dian)(dian)(dian)(dian)方(fang)(fang)式(shi)不同于(yu)其它電(dian)(dian)(dian)(dian)池(chi)。SLA電(dian)(dian)(dian)(dian)池(chi)最好采用(yong)恒(heng)(heng)壓(ya)充(chong)(chong)電(dian)(dian)(dian)(dian)，速率(lv)(lv)通常為(wei)額定容量的(de)1/10(C/10)，充(chong)(chong)電(dian)(dian)(dian)(dian)時(shi)間(jian)為(wei)14-16小時(shi)，或(huo)涓流(liu)充(chong)(chong)電(dian)(dian)(dian)(dian)或(huo)浮充(chong)(chong)充(chong)(chong)電(dian)(dian)(dian)(dian)，充(chong)(chong)電(dian)(dian)(dian)(dian)速率(lv)(lv)為(wei)C/20至C/30。NiCd電(dian)(dian)(dian)(dian)池(chi)充(chong)(chong)電(dian)(dian)(dian)(dian)的(de)終(zhong)止推薦采用(yong)-△V的(de)方(fang)(fang)式(shi)，此時(shi)充(chong)(chong)電(dian)(dian)(dian)(dian)器的(de)電(dian)(dian)(dian)(dian)壓(ya)到達峰值。NiMH電(dian)(dian)(dian)(dian)池(chi)由(you)于(yu)其發熱的(de)特(te)點，充(chong)(chong)電(dian)(dian)(dian)(dian)過(guo)程中要(yao)求采用(yong)溫度檢測(ce)，ΔT/Δt為(wei)其首(shou)選方(fang)(fang)式(shi)。特(te)制的(de)快(kuai)充(chong)(chong)式(shi)NiCd和(he)NiMH電(dian)(dian)(dian)(dian)池(chi)可(ke)在C/2-C/3的(de)速率(lv)(lv)下充(chong)(chong)電(dian)(dian)(dian)(dian)4-6小時(shi)。極低阻尼鎳電(dian)(dian)(dian)(dian)池(chi)作為(wei)快(kuai)充(chong)(chong)式(shi)電(dian)(dian)(dian)(dian)池(chi)的(de)一種，可(ke)在1C速率(lv)(lv)下充(chong)(chong)電(dian)(dian)(dian)(dian)1小時(shi)。最后，鋰離(li)子(zi)電(dian)(dian)(dian)(dian)池(chi)建議采用(yong)恒(heng)(heng)流(liu)/恒(heng)(heng)壓(ya)充(chong)(chong)電(dian)(dian)(dian)(dian)(CC/CV)。

    通(tong)常，鋰(li)離子電(dian)(dian)池供電(dian)(dian)的(de)器械以1C的(de)速率充(chong)(chong)電(dian)(dian)60-75分鐘(zhong)至(zhi)(zhi)4.1V后，即(ji)可(ke)從原(yuan)來的(de)低能(neng)狀(zhuang)態達到電(dian)(dian)量(liang)80-90%的(de)狀(zhuang)態。其它電(dian)(dian)池，除可(ke)采用高電(dian)(dian)流充(chong)(chong)電(dian)(dian)的(de)特制電(dian)(dian)池外，同樣充(chong)(chong)電(dian)(dian)至(zhi)(zhi)80-90%時(shi)可(ke)能(neng)需要更多的(de)時(shi)間。

   鋰離子電(dian)池還需慢充(chong)4-5小時(shi)至(zhi)4.2V，獲(huo)得剩(sheng)余的10-20%的電(dian)量(liang)。這種充(chong)電(dian)方式(shi)有兩(liang)個(ge)好處(chu)。用戶可以(yi)在(zai)極短的時(shi)間內獲(huo)得接近滿充(chong)的電(dian)量(liang)，且充(chong)電(dian)完成(cheng)后的實際(ji)電(dian)壓絕(jue)不會超過(guo)4.2V。

    須注意(yi)的是：如果僅將鋰(li)離(li)子(zi)(zi)(zi)(zi)電(dian)(dian)(dian)(dian)池(chi)充(chong)(chong)至(zhi)4.1V而非4.2V，可延長其循環壽命；但其每次可用(yong)的電(dian)(dian)(dian)(dian)量(liang)將會下(xia)降(jiang)。在(zai)某些醫療(liao)(liao)器(qi)械(xie)中電(dian)(dian)(dian)(dian)池(chi)是一種(zhong)后(hou)備裝置，它始終(zhong)保(bao)持充(chong)(chong)電(dian)(dian)(dian)(dian)的狀(zhuang)態，以(yi)保(bao)證隨(sui)時可用(yong)。鋰(li)離(li)子(zi)(zi)(zi)(zi)的化學性質決定(ding)其不(bu)(bu)適合采(cai)用(yong)涓流充(chong)(chong)電(dian)(dian)(dian)(dian)；鋰(li)離(li)子(zi)(zi)(zi)(zi)電(dian)(dian)(dian)(dian)池(chi)不(bu)(bu)能采(cai)用(yong)恒(heng)定(ding)浮充(chong)(chong)充(chong)(chong)電(dian)(dian)(dian)(dian)。但有幾種(zhong)方(fang)法可以(yi)在(zai)不(bu)(bu)損害電(dian)(dian)(dian)(dian)池(chi)或影響(xiang)醫療(liao)(liao)器(qi)械(xie)的基礎(chu)上，有效降(jiang)低鋰(li)離(li)子(zi)(zi)(zi)(zi)電(dian)(dian)(dian)(dian)池(chi)過度(du)充(chong)(chong)電(dian)(dian)(dian)(dian)的可能性。方(fang)法之一是在(zai)觸(chu)發電(dian)(dian)(dian)(dian)池(chi)再次充(chong)(chong)電(dian)(dian)(dian)(dian)前確保(bao)電(dian)(dian)(dian)(dian)池(chi)放電(dian)(dian)(dian)(dian)量(liang)至(zhi)少為20%，隨(sui)后(hou)進行標(biao)準(zhun)充(chong)(chong)電(dian)(dian)(dian)(dian)。鋰(li)離(li)子(zi)(zi)(zi)(zi)技術(shu)與SLA相(xiang)比顯著提高(gao)了能量(liang)密(mi)度(du)，在(zai)大多(duo)數情況下(xia)足以(yi)防止鋰(li)離(li)子(zi)(zi)(zi)(zi)電(dian)(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)(dian)量(liang)完全充(chong)(chong)滿。

    安全電路

    每種電(dian)(dian)(dian)池(chi)技術均有其(qi)一整套安(an)全考慮。NiCd電(dian)(dian)(dian)池(chi)組帶(dai)有某種電(dian)(dian)(dian)流(liu)分斷設備(bei)以(yi)防止發生嚴重(zhong)故障，這(zhe)(zhe)是優秀的(de)電(dian)(dian)(dian)池(chi)設計必不可少的(de)。NiMH具(ju)有發熱的(de)化學性質(zhi)，因此電(dian)(dian)(dian)池(chi)中(zhong)需配有熱量感應設備(bei)，與充(chong)電(dian)(dian)(dian)器相聯系，防止過度充(chong)電(dian)(dian)(dian)，電(dian)(dian)(dian)池(chi)組本身(shen)還帶(dai)有電(dian)(dian)(dian)流(liu)分斷設備(bei)。在(zai)鋰離子電(dian)(dian)(dian)池(chi)組中(zhong)，一旦發生過電(dian)(dian)(dian)壓(ya)，即有鋰金屬產生。這(zhe)(zhe)說明電(dian)(dian)(dian)池(chi)中(zhong)應使(shi)用安(an)全電(dian)(dian)(dian)路，使(shi)充(chong)放電(dian)(dian)(dian)過程中(zhong)電(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)壓(ya)保持在(zai)特定(ding)的(de)范(fan)圍內(見圖3)。

    圖3.鋰離(li)子(zi)電池(chi)組(zu)設計中需要采用電子(zi)安全裝置(zhi)。電池(chi)組(zu)內還(huan)包(bao)含(han)電量(liang)監測(ce)裝置(zhi)和充電電路。

    雖(sui)然SLA電(dian)(dian)池(chi)一般不(bu)需(xu)要外部(bu)安全(quan)元件，但(dan)許多醫(yi)療設備制造商仍堅持將不(bu)可(ke)(ke)復位保(bao)險(xian)絲置于(yu)(yu)(yu)(yu)電(dian)(dian)池(chi)內部(bu)或(huo)周圍。由于(yu)(yu)(yu)(yu)大部(bu)分SLA電(dian)(dian)池(chi)都帶有(you)突出(chu)的(de)正負(fu)極板，如果沒有(you)保(bao)險(xian)絲，當其(qi)置于(yu)(yu)(yu)(yu)金(jin)屬(shu)板上時，就(jiu)很容易發(fa)生(sheng)短路(lu)，而金(jin)屬(shu)板大量存在(zai)于(yu)(yu)(yu)(yu)醫(yi)療保(bao)健設備中。這些(xie)電(dian)(dian)池(chi)還可(ke)(ke)能(neng)出(chu)現其(qi)它(ta)短路(lu)的(de)危險(xian)。如果發(fa)生(sheng)短路(lu)，裝置即(ji)有(you)爆炸的(de)可(ke)(ke)能(neng)。鋰離子電(dian)(dian)池(chi)組(zu)短路(lu)的(de)危險(xian)較小，安全(quan)電(dian)(dian)路(lu)主(zhu)要用于(yu)(yu)(yu)(yu)保(bao)護電(dian)(dian)池(chi)。

    在電(dian)池(chi)(chi)中(zhong)加入安(an)全電(dian)路增加了器(qi)械的(de)(de)(de)成本，耗費了更(geng)多(duo)(duo)的(de)(de)(de)空間。設計者必(bi)須認識到(dao)這些都是(shi)電(dian)池(chi)(chi)的(de)(de)(de)選(xuan)擇過程中(zhong)會考(kao)慮到(dao)的(de)(de)(de)權衡因素。總的(de)(de)(de)來說，盡管有安(an)全電(dian)路的(de)(de)(de)存在，鋰離(li)子電(dian)池(chi)(chi)仍可以縮小電(dian)池(chi)(chi)組體(ti)積，減輕其重量(liang)，并能(neng)釋(shi)放更(geng)多(duo)(duo)的(de)(de)(de)能(neng)量(liang)。

    電量監測

    來(lai)越(yue)多的醫療器械(xie)制造商(shang)開始采用鋰(li)離子技術，電(dian)(dian)池(chi)管(guan)理(li)特性(xing)(xing)在行業中也越(yue)來(lai)越(yue)常見。電(dian)(dian)量監測設備可以為(wei)終端用戶提(ti)供一些(xie)信息，如電(dian)(dian)池(chi)預計使用時間(jian)等。管(guan)理(li)特性(xing)(xing)的引入，很大程度上明確(que)了(le)電(dian)(dian)池(chi)電(dian)(dian)量評估及充(chong)電(dian)(dian)方(fang)案的執行。

    就(jiu)電(dian)(dian)池管理而言(yan)，使用(yong)鋰離子(zi)電(dian)(dian)池的設(she)計者有多種(zhong)選擇方(fang)案。例如，一些(xie)鋰離子(zi)電(dian)(dian)池電(dian)(dian)量監測設(she)備(bei)中含(han)有信息(xi)特征(zheng)，可以報(bao)告已經過的充放(fang)電(dian)(dian)循環次數。此類信息(xi)在一些(xie)重要(yao)的醫療設(she)備(bei)中具有重要(yao)作用(yong)。電(dian)(dian)量監測基本方(fang)法有兩種(zhong)：基于電(dian)(dian)壓和庫侖計數。將兩種(zhong)技術(shu)相結合(he)的解(jie)決方(fang)案，其(qi)準確(que)性高達99%。

    耐高(gao)溫性

    鋰離子電池在40°-45°C的高(gao)溫條件(jian)下，性(xing)能(neng)優于其(qi)它(ta)電池。SLA和NiMH電池在高(gao)熱量環境下無法正常工作。這成(cheng)為其(qi)在急(ji)救(jiu)工具中使用(yong)的一(yi)個(ge)限制因素，因為此時，使用(yong)者無法將他們的便攜(xie)式(shi)器械保存在低溫環境下。

    在為便攜式器(qi)械選擇最佳(jia)電源(yuan)方案時，必須對(dui)其總成本和(he)整(zheng)體(ti)性能進行評(ping)估。

    鋰(li)離子技術(shu)的高電(dian)壓(ya)特(te)性可(ke)以(yi)減(jian)少電(dian)池使用(yong)(yong)量，由此(ci)降低(di)了電(dian)池組的成(cheng)本(ben)，使之與使用(yong)(yong)鎳技術(shu)的電(dian)池大致相當。此(ci)外(wai)，鋰(li)離子電(dian)池供應商不斷使用(yong)(yong)新材料(liao)，以(yi)降低(di)電(dian)池成(cheng)本(ben)。

    鋰離子電池體積小、重量輕、能量高、循(xun)環壽命(ming)長、耐久性(xing)好、電壓高及耐熱(re)性(xing)好的(de)特(te)點使其(qi)具有潛在的(de)優勢。醫療(liao)電子產品制造商可(ke)以利用這些特(te)性(xing)，拓(tuo)寬產品市場，并(bing)最終給消費者、醫療(liao)專業人員和病人帶來治療(liao)等方(fang)面的(de)好處。