Battery Handbook

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ENERGIZERBATTERYMANUFACTURING
VERSION1.2
3.4‐‐Multi‐BatteryApplications
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In some situations, a higher voltage or an increased performance level is desired for a certain
application.ZincAirbatteries canbearrangedinseriesorinparallelasneeded.Devicesthatusemore
thanoneZincAirPrismaticbattery introduce additional design considerations.An air plenum andair
access
 is required for each battery, and these can be independent or shared.Additionally, stacked
batteriesrequirespaceabovetheairholesideofeachbattery.Iftwobatteriesarestackedwiththeair
holesidesfacingeachother,thenasingleairplenumcanbeused.
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3.5‐‐RecommendedCutoffVoltage
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TherecommendedendoflifeforZincAirbatteriesisat0.9voltswhereessentiallyallavailablecapacity
hasbeenused.Below0.9voltsadditionalchemicalreactionsmaytakeplaceinthebatterywhichcan
leadtoincreasedpotentialforgassingandleakage.Energizerrecommendsthatdevicesaredesignedto
prevent
thebatteryfrom being discharged below0.9volts.Thiscanbe accomplished preferablybya
completedisconnectofthebatterycircuitorbyusingalowvoltagebatterywarning.
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3.6‐‐FuelGauging
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ZincAirPrismaticbatterieshavea relativelyflatdischargecurvecomparedtoexistingAlkalinesolutions,
withthedischargecurveslopingmoreatincreaseddischargerates.ThiscanbeseeninFigure 4 and
Figure6.AlthoughtherelativelyflatdischargecurvemakestheZincAirsystemmorechall engingto
fuel
gauge with conventional  voltage‐only measurements, the flat voltage profile  helps make device
performance consistent throughout the life of the battery.A more sophisticated algorithm
incorporating additional measurements that are tailored to the specific application may be necessary.
This is similar to what is required for Lithium Iron Disulfide and
 rechargeable Nickel Metal Hydride
batteries.