Post by thread:[OT] Rechargeable Battery Dangers

>Radioactive emission?! I wasn't aware that Li ion batteries >contained any radioactive materials! If so, why would it have to? It >is a purely chemical process,right? I think he meant hazardous. Lithium metal is very reactive, its a chemical burn hazard, like acids. If you were to disassemble a Lithium / Ion battery, you could definitely hurt yourself. With Nickel / Cadmium, the problem is the Cadmium. Cadmium, much like Mercury, is actually toxic. I know that Mercury is a neurotoxin, it causes brain damage. Hence the banning of lead in paints. I'm not sure if Cadmium's effects are similar or not, but I don't want to find out on me or my kids. So Cadmium makes NiCd batteries hazardous waste. One definitely should not discard NiCd batteries in regular trash! I don't know if Lithium bearing batteries are considered hazardous. Certainly most consumers don't know the difference, so I suspect regulations treat NiCd and Li-ion the same. ------------ Barry King, KA1NLH Engineering Manager NRG Systems "Measuring the Wind's Energy" Hinesburg, Vermont, USA spam_OUTbarryTakeThisOuTnrgsystems.com "The witty saying has been deleted due to limited EPROM space"

Barry King wrote: > > I don't know if Lithium bearing batteries are considered hazardous. > Certainly most consumers don't know the difference, so I suspect > regulations treat NiCd and Li-ion the same. > For shipping and disposal, lithium batteries are considered hazardous goods, but only if the lithium contents exceeds a certain amount per cell. The "C" cells that we use are OK to ship, but need paperwork. "AA" (or is that "AAA"?) cells don't contain enough lithium and button cells aren't even in the picture. BTW, lithium cells are *extremely* explosive when heated. Years ago, we saw a film produced by Electrochem that showed a "D" cell being heated in an environmental chamber. When it exploded, it blew out the chamber's ventilation grill, leaving it across the room. --Matt

<x-rich>At 02:13 PM 6/16/99 -0600, you wrote: {Quote hidden}>Barry King wrote: >> >> I don't know if Lithium bearing batteries are considered hazardous. >> Certainly most consumers don't know the difference, so I suspect >> regulations treat NiCd and Li-ion the same. >> >For shipping and disposal, lithium batteries are considered hazardous >goods, but only if the lithium contents exceeds a certain amount per >cell. The "C" cells that we use are OK to ship, but need paperwork. >"AA" (or is that "AAA"?) cells don't contain enough lithium and button >cells aren't even in the picture. > >BTW, lithium cells are *extremely* explosive when heated. Years ago, we >saw a film produced by Electrochem that showed a "D" cell being heated >in an environmental chamber. When it exploded, it blew out the >chamber's ventilation grill, leaving it across the room. Hi... We've got a low power data logger that may need to see service in hazardous environments... Do you have any sources for <bold>documented </bold>failure modes for the various types of batteries? The manufacturer's--probably for liability reasons--don't seem to want to part with real information. We want to use standard alkaline and non-rechargeable lithium 9-volt batteries but need some real information with the name of a test lab or manufacturer on it as the author/responsible party. I have been told NiCd are ruled out completely due to their known explosive failure modes on heating or very rapid discharge (self heating). I have also been told that standard lithium's do not have this problem. I do know that the rechargeable lithiums have some not-nice failure modes, and have heard stories about meltdowns in laptops--which could be VERY not-nice if it happens in your lap. Kelly ******************************************************************************** **** All legitimate attachments to this email will be clearly identified in the text. William K. Borsum, P.E. OEM Dataloggers and Instrumentation Systems <<.....borsumKILLspam@spam@dascor.com> & <<http://www.dascor.com> </x-rich>

{Quote hidden}> >Hi... > >We've got a low power data logger that may need to see service in >hazardous environments... > >Do you have any sources for <bold>documented </bold>failure modes for the >various types of batteries? > >The manufacturer's--probably for liability reasons--don't seem to want to >part with real information. > >We want to use standard alkaline and non-rechargeable lithium 9-volt >batteries but need some real > >information with the name of a test lab or manufacturer on it as the >author/responsible party. > > >I have been told NiCd are ruled out completely due to their known >explosive failure modes on heating or > >very rapid discharge (self heating). I have also been told that standard >lithium's do not have this problem. >I do know that the rechargeable lithiums have some not-nice failure >modes, and have heard > >stories about meltdowns in laptops--which could be VERY not-nice if it >happens in your lap. > > >Kelly If by hazardous environments you mean potentially explosive atmospheres, there are standards and approval procedures for this type of device, and batteries are by no means the only issues. Depending on the exact nature of the device and hazard, devices should either be explosion proof (big heavy sealed casing so if gas gets in and ignites the flame will not get out), or intrinsically safe (energies controlled to avoid ignition under fault conditions). I have some experience designing intrinsically-safe devices for UL913 (US) or EN50020 (EU) standards. The battery testing procedures for these standards seem a little haphazard, but is probably about all you can do in practice. Basically you have to specify exactly which battery & manufacturer you will be using, take several samples and short them out, measuring the temperature rise. Any safety devices must be bypassed, In many cases you need to encapsulate the battery pack, due to the spark hazard, as creepage distances across the terminals are usually insufficient to meet the standard. This procedure does not seem to cope with manufacturers 'improving' their product, which is a little worrying, but you will not find a manufacturer who guarantees fault performance. 9V alkaline cells are no problem (T4 classification), provided the battery is not removable in the hazardous zone. It is certainly possible to use nicad and ni-mh D cells, but these will probably need to be potted. We did start looking at lithium-ion D cells, but I think there were problems with these (You can't rely on the pack protection electronics under fault conditions).