Maxwell超級(jí)電容

1、Ultracapacitors l Microelectronics l High-Voltage Capacitors特卡特培訓(xùn)特卡特培訓(xùn)By:麥克斯維爾技術(shù) - 圣地亞哥Ultracapacitors l Microelectronics l High-Voltage CapacitorsAbout Maxwell電容器制造始于生產(chǎn)設(shè)施：歐美及亞洲麥克斯維爾是創(chuàng)新、高能效儲(chǔ)存及能源輸送解決方案的領(lǐng)先開(kāi)發(fā)者及生產(chǎn)者認(rèn)證:ISO 9001:2000ISO/TS 16949ISO 9002Ultracapacitors l Microelectronics l High-Voltage Capa

2、citorsTable of Content什么時(shí)候我可以用超級(jí)電容?什么事超級(jí)電容?超級(jí)電容市場(chǎng)超級(jí)電容應(yīng)用規(guī)范你的系統(tǒng)Sizing your SystemSizing Examples超級(jí)電容系統(tǒng)設(shè)計(jì)指引摘要Ultracapacitors l Microelectronics l High-Voltage Capacitors什么時(shí)候我可以用超級(jí)電容什么時(shí)候我可以用超級(jí)電容? 需要高度可靠后備電力的應(yīng)用。 1-60秒短時(shí)橋接電力，用于轉(zhuǎn)換到第二個(gè)電源或順序關(guān)閉 很好地補(bǔ)償瞬時(shí)嚴(yán)重電壓凹陷的優(yōu)質(zhì)電力 針對(duì)大瞬時(shí)高峰或電能浪涌的電力緩沖器Ultracapacitors l Microelect

3、ronics l High-Voltage Capacitors電力電力 vs 能量能量電力和能源有什么不同?Ultracapacitors l Microelectronics l High-Voltage Capacitors應(yīng)用模型應(yīng)用模型Ultracapacitors l Microelectronics l High-Voltage CapacitorsPeak Power Shaving 超級(jí)電容提供尖峰電力 .可獲得電力需要的電力超級(jí)電容尖峰電力削減尖峰電力削減尖峰電力Ultracapacitors l Microelectronics l High-Voltage Capaci

4、torsBack-Up Power Support 超級(jí)電容提供尖峰電力.還有后備電力.需要的電力可獲得的電力超級(jí)電容后備電力后備電力后備電力Ultracapacitors l Microelectronics l High-Voltage Capacitors什么是超級(jí)電容什么是超級(jí)電容?Ultracapacitors l Microelectronics l High-Voltage Capacitors超級(jí)電容的性能特性超級(jí)電容的性能特性 超級(jí)電容的表現(xiàn)在傳統(tǒng)電容器和電化學(xué)單元之間. 快充快放能力 高可逆過(guò)程, 10萬(wàn)個(gè)周期 能力比單元低僅有單元能力的10% 能量比電解電容更高 出色的低

5、溫表現(xiàn)Ultracapacitors l Microelectronics l High-Voltage Capacitors什么是超級(jí)電容什么是超級(jí)電容?C = e er A/dd最小化最小化A最大化最大化E = 1/2 CV2電解質(zhì)金屬箔金屬箔電解質(zhì)ECDL分離器 超級(jí)電容是: 100年的老技術(shù), 因現(xiàn)代材料而加強(qiáng) 基于電解質(zhì)的極化、高表面積電極及極小的充電點(diǎn)和分離 也就是電化學(xué)雙層電容電極 電解質(zhì)ECDL分離器Ultracapacitors l Microelectronics l High-Voltage Capacitors技術(shù)比較技術(shù)比較Ultracapacitors l Micr

6、oelectronics l High-Voltage Capacitors技術(shù)比較技術(shù)比較 (page 2)0,010,1110100100010100100010000動(dòng)力或電力密度動(dòng)力或電力密度/W/kg能量密度能量密度/Wh/kg雙層電容器雙層電容器10h1h0,1h36sec3,6sec0,36sec36msec鉛酸單元鉛酸單元 Ni/CdLi-單元單元Al-ElcoU/C燃料單元Ultracapacitors l Microelectronics l High-Voltage Capacitors超級(jí)電容超級(jí)電容 vs 單元技術(shù)單元技術(shù)Ultracapacitors l Micro

7、electronics l High-Voltage Capacitors超級(jí)電容市場(chǎng)超級(jí)電容市場(chǎng)Ultracapacitors l Microelectronics l High-Voltage Capacitors超級(jí)電容市場(chǎng)超級(jí)電容市場(chǎng)超級(jí)電容全球市場(chǎng)消費(fèi)品數(shù)碼相機(jī)PDA玩具記憶備份應(yīng)急電源UPS風(fēng)力發(fā)電工業(yè)固定式燃料單元自動(dòng)化/機(jī)器人運(yùn)輸電動(dòng)巴士/卡車發(fā)動(dòng)機(jī)啟動(dòng)輕量電動(dòng)車當(dāng)?shù)仉娏﹁F路Ultracapacitors l Microelectronics l High-Voltage Capacitors已有產(chǎn)品已有產(chǎn)品 Available Products含水電解質(zhì)含水電解質(zhì): ESMA

8、, Elit, Evan, Skeleton Technologies and Tavrima 優(yōu)勢(shì): 高電解導(dǎo)電率 不需緊密密封以隔離 低環(huán)境影響 弱勢(shì): 低分解電壓 (1.23V) 窄的工作區(qū)間(水的冰點(diǎn))有機(jī)電解質(zhì)有機(jī)電解質(zhì): Maxwell Technologies, Panasonic, EPCOS, Ness Capacitors, ASAHI GLASS 優(yōu)勢(shì): 高分解電壓 寬的工作電壓 弱勢(shì): 低電解導(dǎo)電率 需要緊密密封，隔離濕氣Ultracapacitors l Microelectronics l High-Voltage Capacitors超級(jí)電容應(yīng)用超級(jí)電容應(yīng)用Ult

9、racapacitors l Microelectronics l High-Voltage Capacitors應(yīng)用應(yīng)用汽車汽車 14/42 V系統(tǒng) HEV 電力子系統(tǒng)牽引牽引Traction 回復(fù)制動(dòng) 電壓穩(wěn)定 柴油機(jī)啟動(dòng)工業(yè)工業(yè) 電力質(zhì)量 Pitch systems Actuators消費(fèi)電子消費(fèi)電子 AMR PDAs 數(shù)碼相機(jī) 對(duì)講機(jī) 掃描器 玩具小單元小單元大單元大單元Ultracapacitors l Microelectronics l High-Voltage Capacitors電力機(jī)車包電力機(jī)車包制動(dòng)能源收集柴油機(jī)啟動(dòng)今日市場(chǎng)今日市場(chǎng)風(fēng)電廠風(fēng)漿系統(tǒng)風(fēng)電廠風(fēng)漿系統(tǒng)突發(fā)電力Bu

10、rst power小單元應(yīng)用小單元應(yīng)用Digital cameras, AMR, Actuators, Memory boards牽引牽引工業(yè)消費(fèi)者消費(fèi)者 Ultracapacitors l Microelectronics l High-Voltage CapacitorsUltracapacitors l Microelectronics l High-Voltage Capacitors儲(chǔ)能系統(tǒng)儲(chǔ)能系統(tǒng): 基站或在車上基站或在車上時(shí)間時(shí)間 t11號(hào)車剎車 儲(chǔ)能系統(tǒng)儲(chǔ)存剎車能量時(shí)間時(shí)間 t22號(hào)車加速 儲(chǔ)能系統(tǒng)放出能量SITRAS SES - 解決方案解決方案優(yōu)勢(shì)優(yōu)勢(shì): 通過(guò)減少一次能源消

11、耗降低成本應(yīng)用應(yīng)用: 交替送出儲(chǔ)存的剎車能量，用于車輛再加速解決方案解決方案: 可以提供基站式或車上儲(chǔ)存系統(tǒng)Ultracapacitors l Microelectronics l High-Voltage CapacitorsSITRAS SES - 益處益處Saved energyReduction of the power need by 50 kWEnergy saving of 340.000 kWh per year and per installationthermal limit68 kWh/h04.08.0107.08.0110.08.0113.08.015040302010

12、0kWh/hSaved energyReduction of the power need by 50 kWEnergy saving of 340.000 kWh per year and per installationthermal limit68 kWh/h04.08.0107.08.0110.08.0113.08.0150403020100kWh/h04.08.0107.08.0110.08.0113.08.0150403020100kWh/hUltracapacitors l Microelectronics l High-Voltage Capacitors龐巴迪運(yùn)輸系統(tǒng)的龐巴迪

13、運(yùn)輸系統(tǒng)的MITRAC MITRAC energy saverUltracapacitors l Microelectronics l High-Voltage Capacitors柴油發(fā)動(dòng)機(jī)的啟動(dòng)柴油發(fā)動(dòng)機(jī)的啟動(dòng) by Stadler柴油引擎車輛用的超級(jí)電容模塊柴油引擎車輛用的超級(jí)電容模塊 電壓平衡的結(jié)實(shí)構(gòu)造 容易放大以適應(yīng)額外的啟動(dòng)電力 容易與現(xiàn)有機(jī)殼集成 容易使用，免維護(hù)Ultracapacitors l Microelectronics l High-Voltage Capacitors風(fēng)力發(fā)電機(jī)變槳系統(tǒng)風(fēng)力發(fā)電機(jī)變槳系統(tǒng)現(xiàn)代風(fēng)力渦輪機(jī) 由三葉可變速 渦輪構(gòu)成 獨(dú)立的機(jī)電 推動(dòng)裝置 控

14、制和調(diào)節(jié) 旋翼槳葉最新技術(shù) uses the wind not only to produce wind energy but also for its own safety Ultracapacitors l Microelectronics l High-Voltage Capacitors變槳系統(tǒng)儲(chǔ)能裝置變槳系統(tǒng)儲(chǔ)能裝置每個(gè)變槳系統(tǒng)配有一個(gè)超級(jí)電容緊急供電裝置超級(jí)電容因如下原因代表著一個(gè)理想的應(yīng)急供能系統(tǒng)： 提高了安全水平 高可靠性 效率 可擴(kuò)展性75 V, 81 F 超級(jí)電容模塊超級(jí)電容模塊4 模塊串聯(lián)驅(qū)動(dòng)模塊串聯(lián)驅(qū)動(dòng)300 V 3-5 MW風(fēng)電場(chǎng)的風(fēng)電場(chǎng)的變槳距系統(tǒng)變槳距系統(tǒng) 開(kāi)關(guān)盒

15、開(kāi)關(guān)盒包含包含2600F的的超級(jí)電容超級(jí)電容Ultracapacitors l Microelectronics l High-Voltage Capacitors能量單元驅(qū)動(dòng)的叉車能量單元驅(qū)動(dòng)的叉車裝有能量單元的叉車單元系統(tǒng)級(jí)超級(jí)電容模塊BOOSTCAP module:48 BCAP0010112 V, 55 F40 kW 尖峰電力Ultracapacitors l Microelectronics l High-Voltage Capacitors超級(jí)電容在汽車上的應(yīng)用超級(jí)電容在汽車上的應(yīng)用 Distributed energy modules are located at the act

16、uator level in the vehicle control hierarchy in close proximity to the actuator power driver (should be within 18”).Vehicle SystemControllerISG SubsystemBelt or CrankshaftEngineTransmissionHigh VoltageBattery Primary StorageOther 42VLoadsBrake actuatorsETC, Fan, Water PumpISGTorqueGear Sel, L/U Clut

17、chOil PumpSOC, SOH,VsysContinuous,Scheduled,SelectableBrakesRegen Brake SysSteeringelectric assistSteering actuatorUCUCUCECUMtrRackECUHCUECUMtrThrottleBodySteeringWheelBrakePedalAccelPedalPower & Communications (PDA)DistributedEnergy StorageModulesEnergy StorageSystem MgmtUCUCECUHVACElectric air

18、cond. comp.Ultracapacitors l Microelectronics l High-Voltage Capacitors帶超級(jí)電容的能量單元帶超級(jí)電容的能量單元超級(jí)電容已被接受為燃料單元普通儲(chǔ)能方式之一超級(jí)電容已被接受為燃料單元普通儲(chǔ)能方式之一每一個(gè)每一個(gè) 全球主要車廠都在測(cè)試燃料單元 作為傳動(dòng)動(dòng)力系統(tǒng)的替代方案之一。所有值得關(guān)注的所有值得關(guān)注的 燃料單元公司正在用或在試驗(yàn)采用超級(jí)電容作為系統(tǒng)的集成部分.多家多家 主要汽車廠聲明了將帶超級(jí)電容的燃料單元作為他們的基本系統(tǒng)架構(gòu)。本田和現(xiàn)代已經(jīng)公開(kāi)，其它和我們合作的還沒(méi)有?！袄贸?jí)電容使我們獲得了能效優(yōu)勢(shì)，油門響應(yīng)and t

19、hrottle responsiveness over competitors that are pursuing the hybrid batteryfuel cell model”本田汽車公司本田汽車公司Ultracapacitors l Microelectronics l High-Voltage CapacitorsSizing Your SystemUltracapacitors l Microelectronics l High-Voltage Capacitors數(shù)據(jù)表數(shù)據(jù)表Ultracapacitors l Microelectronics l High-Voltage Ca

20、pacitors數(shù)據(jù)表數(shù)據(jù)表Ultracapacitors l Microelectronics l High-Voltage Capacitors如何檢測(cè)超級(jí)電容如何檢測(cè)超級(jí)電容 檢測(cè)超級(jí)電容你需要:雙向電源 (supply/load) OR separate power supply and programmable load (constant current capable) voltage vs. time measurement and recording device (digital scope or other data acquisition) 電容和電阻Capacitan

21、ce and Resistance:電容電容Capacitance = (Id * td)/(Vw - Vf) = (Id * td)/VdESR = (Vf - Vmin)/Id Vw = initial working voltage Vmin = minimum voltage under loadId = discharge current Vf = voltage 5 seconds after removal of load.td = time to discharge from initial voltage to minimum voltageUltracapacitors l

22、 Microelectronics l High-Voltage Capacitors基本公式基本公式電容的定義:C = Q/V (1)Charge = current * time: Q = I*t C = I*t/V (1a) Solving for voltage:V = I*t/C (2)動(dòng)態(tài)電壓:dV/dt = I/C (3)儲(chǔ)存能源E = C*V2 (4)At initial voltage Vo,Eo = C*Vo2At final voltage Vf, Ef = C*Vf2Delivered energy = Eo Ef E = C*(Vo2 Vf2) (5)Ultracap

23、acitors l Microelectronics l High-Voltage Capacitors電壓電壓 & 電流電流 vs. 時(shí)間時(shí)間C = 15 farad; Resr = 100 milliohmVo = 48V; I = 30A-5-4-3-2-10123456789101112131415Time (sec)20253035404550Voltage (V)05101520253035404550Current (A)- Resr+C-iVoltageCurrentVoVminVfV = Q/CdVesr = I*ResrdV/dt = I/C ; dV = I*dt

24、/CdVtotal = I*dt/C + I*ResrE = C*(Vo2 Vf2)Ultracapacitors l Microelectronics l High-Voltage Capacitors基本模型基本模型 Series/Parallel configurations Changes capacitor size; profiles are the same 串聯(lián)配置Series configurationsCapacitance decreases, Series Resistance increasesCs=Ccell/(#of cells in series)Rs=Rcel

25、l*(# of cells in series) 平行配置Parallel configurationsCapacitance increases, Series Resistance decreasesCP=Ccell*(# of cells in parallel)RP=Rcell/(# cells in parallel) 受控電流 Use output current profile to determine dV/dtdV = I * (dt/C + ESR) 受控電力 Several ways to look at this:Pterm = I*Vcap I2*ESR (solve

26、 quadratic for I)I = Vcap - sqrt(Vcap2-4*ESR*Pterm)/(2*ESR) Solve for dV/dt as in current-controlled J=W*s=1/2CV2 Solve for C.Ultracapacitors l Microelectronics l High-Voltage Capacitors帶單個(gè)儲(chǔ)能裝置的應(yīng)用帶單個(gè)儲(chǔ)能裝置的應(yīng)用 Applications in which little total energy is required (i.e. memory backup) Possibly used with

27、 other energy sources Short duration, high power (i.e. pulse transmit) Long duration, low power (i.e UPS backup) Opportunities for high charge rates (i.e toys)Ultracapacitors l Microelectronics l High-Voltage Capacitors帶兩個(gè)儲(chǔ)能裝置的應(yīng)用帶兩個(gè)儲(chǔ)能裝置的應(yīng)用 Power vs. Energy design tradewhen using two components 單原件與雙

28、原件的比對(duì) Engines/Fuel cells/Batteries/Solar Arrays are energy rich/power poor (or poor response) Size these components for enough energy, system may be limited in power Size these components for power, system may have surplus of energy Ultracapacitors are power rich/energy poor Size an ultracapacitor f

29、or enough energy, system may have a surplus of power Size an ultracapacitor for power, system may be limited in energy 雙元件Two components A primary source for energy; Ultracapacitor for power Requires appropriate definition of peak power vs. continuous powerUltracapacitors l Microelectronics l High-V

30、oltage Capacitors超級(jí)電容的老化超級(jí)電容的老化 Unlike batteries, Ultracapacitors do not have a hard end of life criteria. Ultracapacitors degradation is apparent by a gradual loss of capacitance and a gradual increase in resistance. End of life is when the capacitance and resistance is out of the application range

31、 and will differ depending on the application. Therefore life prediction is easily done.Ultracapacitors l Microelectronics l High-Voltage Capacitors電容和電容和 ESR vs 頻率頻率ESR vs . Frequency0,00E+001,00E-042,00E-043,00E-044,00E-045,00E-046,00E-047,00E-041,00E-021,00E-011,00E+00 1,00E+01 1,00E+02 1,00E+03F

32、requency HzESR mOhmCapacitance vs. Frequency0,00E+005,00E+021,00E+031,50E+032,00E+032,50E+033,00E+033,50E+031,00E-021,00E-011,00E+001,00E+011,00E+021,00E+03Frequency HzCapacitance FUltracapacitors l Microelectronics l High-Voltage CapacitorsC and ESR Temperature DependencyTemperature CESR mOhmCapaci

33、tance FUltracapacitors l Microelectronics l High-Voltage CapacitorsBCAP 自放電自放電Self Discharge vs Temperature30,040,050,060,070,080,090,0100,0024681012141618202224262830Time days% U (t = 0) - 35 C + 5 C + 25 C + 65 CUltracapacitors l Microelectronics l High-Voltage CapacitorsBCAP 循環(huán)能力循環(huán)能力90 A CC, 1.15

34、-2.3 V, 25 s, RT50.060.070.080.090.0100.0110.0020000400006000080000100000Cycle NumberChange in Capacitance %0.0E+002.0E-044.0E-046.0E-048.0E-041.0E-031.2E-031.4E-031.6E-031.8E-032.0E-03ESR OhmESRCapacitanceUltracapacitors l Microelectronics l High-Voltage CapacitorsBCAP Cycling500000 cycles between

35、1.8 and 2.7 V, 100 AESR (1 Hz) increase 140 % (0.49 to 0.79 mOhm Capacitance decrease 38 % (2760 to 1780 F), 30% compared to rated capacitanceUltracapacitors l Microelectronics l High-Voltage CapacitorsBCAP 直流壽命直流壽命 DC LifeCapacitance and ESR variation at U, T = 40 C50,055,060,065,070,075,080,085,09

36、0,095,0100,0105,00,0100,0200,0300,0400,0duration days% C (t = 0)2.5V 40C2.1V 40C2.3V 40C-40,0-20,00,020,040,060,080,0100,0120,0140,0160,0180,0200,00,0100,0200,0300,0400,0duration days% ESR (t = 0)2.5V 40C2.1V 40C2.3V 40CUltracapacitors l Microelectronics l High-Voltage CapacitorsBCAP DC Life 0,020,0

37、40,060,080,0100,0120,00100200300400duration days% C (t = 0)2.1V 65C2.3V 65C2.5V 65C-40,0-20,00,020,040,060,080,0100,0120,00100200300400duration days% ESR (t = 0)2.5V 65C2.1V 65C2.3V 65CCapacitance and ESR variation at U, T = 65 CUltracapacitors l Microelectronics l High-Voltage Capacitors選型舉例選型舉例Ult

38、racapacitors l Microelectronics l High-Voltage Capacitors Example sizing1) 定義系統(tǒng)需要15 W delivered for 10 seconds10V max; 5V min2) 確定總能量需求: J=WS=10W*10sec=150Ja) Determine Capacitance based on:J=1/2CV2b) Substitute the energy from above:150J=1/2C(Vmax2-Vmin2)c) Solve for C:C=300/(102-52)=4F3) 加20-40% 安

39、全余量以覆蓋I2R 損失Csystem = 4.8F4) 計(jì)算串聯(lián)組中需要多少個(gè)單元 (因?yàn)樽罡邌卧妷?= 2.5V)10V/2.5V = 串聯(lián)組中需要4個(gè)單元5) Calculate cell-level capacitanceC = Csys * # of series cells = 4.8F* 4 = 19.2F per 2.5V “cell”6) 計(jì)算并聯(lián)單元的數(shù)量 (我們將假定一個(gè)10F單元)# in parallel = 19.2/10F = 2 x 10F cells in parallelUltracapacitors l Microelectronics l High-V

40、oltage Capacitors產(chǎn)品策略產(chǎn)品策略Ultracapacitors l Microelectronics l High-Voltage Capacitors可提供的產(chǎn)品組合可提供的產(chǎn)品組合Enhance application cost effectiveness by filling the product portfolio ladder - Initial focus: MC Series3000 F2600F2000 F1500 F1200 F650 F電力梯級(jí)電力梯級(jí)3000 F2600F2000 F1500 F1200 F650 F能源梯級(jí)能源梯級(jí)11個(gè)新的超級(jí)電容單

41、元個(gè)新的超級(jí)電容單元Ultracapacitors l Microelectronics l High-Voltage CapacitorsMC系列用新產(chǎn)品組合系列用新產(chǎn)品組合 能源能源Energy電力電力Power29個(gè)新產(chǎn)品個(gè)新產(chǎn)品Ultracapacitors l Microelectronics l High-Voltage Capacitors設(shè)計(jì)一個(gè)超級(jí)電容系統(tǒng)的指引設(shè)計(jì)一個(gè)超級(jí)電容系統(tǒng)的指引Ultracapacitors l Microelectronics l High-Voltage Capacitors超級(jí)電容單元的平衡超級(jí)電容單元的平衡為什么要有單元平衡? Achieve

42、 cell to cell voltage balance Accounts for variations in capacitance and leakage current, initial charge and voltage dependent on capacitance, sustained voltage dependent on leakage current Reduces voltage stress on an individual cell Increase overall reliability of the individual cellsUltracapacito

43、rs l Microelectronics l High-Voltage Capacitors超級(jí)電容單元的平衡超級(jí)電容單元的平衡如何進(jìn)行單元平衡? Resistor method, resistor placed in parallel, resistor value calculated at 10 x leakage current for slow balance, 100 x for faster balance, good for low cycle when efficiency or stand by loss not an issueSurface Mount Resisto

44、r for low duty cycle applicationUltracapacitors l Microelectronics l High-Voltage Capacitors超級(jí)電容單元的平衡超級(jí)電容單元的平衡 Active method, use semiconductors to limit or balance voltage between cells, best for high duty cycle or when efficiency and stand by loss from leakage current are important, highest cell r

45、eliability option Active cell to cell balance circuitUltracapacitors l Microelectronics l High-Voltage Capacitors單元平衡單元平衡Low capacitance,high leakage cellNote high and low points;low capacitance cell1.5 hours of Vehicle cycling ( 200A) 低成本 Scalable balance current 10mA, 300mA circuits 很低的quiescent c

46、urrent (20A) No on/off required 模塊化安裝 N cells requires N-1 circuits 電壓獨(dú)立2600F cells; 4 in Series300mA balancer for 50 & 60mm cells10mA balancer for 5F & 10F cellsUltracapacitors l Microelectronics l High-Voltage Capacitors單元平衡單元平衡Three cells with one cell balancing resistor removed:OCTA Cycl

47、es Max. Voltage Profiles0.000.501.001.502.002.503.003.504.004.505.00012345678910Day #Cell voltage (V)C1-VC2-VC3-VUltracapacitors l Microelectronics l High-Voltage Capacitors超級(jí)電容的并組超級(jí)電容的并組為什么要并組? Ensure proper mechanical stress Ensure robust low resistance interconnect Ensure proper electrical isolat

48、ion Ensure proper thermal considerations Ensure agency compliance Increase overall cell reliability Reduce or eliminate maintenance requirementsUltracapacitors l Microelectronics l High-Voltage Capacitors電容單元的并組電容單元的并組如何并組單元? Care should be taken for the electrical interconnect, a few key guidelines

49、 to follow: Do not over torque. Over torque at the terminals may cause internal failure of contact points. For example, the Maxwell BCAP specification is 100 in.-lbs Use similar conductor metal interconnect bus bars to eliminate galvanic corrosion. Good surface to surface contact will reduce inter-cell resistance, reducing voltage drop and temperature stressUltracapacitors l Microelectronics l High-Voltage Capacito