Nerobro <nerobro at gmail.com> wrote: BeLite is using LiPo batteries in their ultralights.
Greg was kind enough to send me a copy of his posting, but I don't see posts on KRnet until the next day. Here was my reply to him: There are several factors here. First, [on the Belite], is the lithium battery a part of an electrical system that includes a generator/alternator for charging? Maybe I missed it, but in a brief look at the Belite website, I didn't see any mention of it. The electronic instruments that they sell are very low drain, and wouldn't require much of a battery, so simply having a battery that is charged on the ground would make sense. Does Belite provide anything but the barest information on the battery, or how to charge it? I thought of Belite as an ultralight, part 103 craft, but it looks like it can be built as an ELSA. They don't have to certify it (that doesn't really make that much difference to a homebuilder), but is the battery used to power the ignition system? Is it used for starting? Both of those instances have completely different requirements. I've been using lithium batteries for years in tools, but they have their own special chargers, and, on the ones I've used on my power tools, they cannot be allowed to run all the way down. They are also very heat sensitive, especially for charging. Where I live, daytime temperatures are often over 110F in the summer. I'm all for innovation and experimenting, but before I'd put a Lithium battery of any kind for my primary battery in an airplane, I'd sure want to know what the limitations are. It cost Boeing multiple millions of dollars because all those questions weren't thoroughly addressed on the Dreamliner. I urge you to read Bob's article. To add to the above: Bob discusses the various factors which have to be considered when using a lithium battery. Among them are the special ways in which the batteries need to be charged. There are many examples of Lithium batteries exotherming to the point that they catch fire when they are being charged. My lithium batteries need to be recharged in a cool place because they have a temperature monitor. Just yesterday, a girl had her phone recharging under her pillow, (phones don't have temperature monitors) and it caught fire when the battery exothermed. All of my lithium batteries for my tools have temperature monitors that don't allow them to be charged over a certain temperature. I have sometimes resorted to putting them into a freezer for a short time so they would be cool enough to charge. Bob Nuckolls article goes much further into the whys and hows of lithium battery usage in airplanes. Everyone is free to do what they wish, but I urge everyone who's thinking of using lithium batteries for their airplane to read the article. On Mon, Jul 28, 2014 at 2:11 PM, Dan Branstrom via KRnet < krnet at list.krnet.org> wrote: >> A while back, one of the posters here was interested in using a much >> lighter Lithium battery for their plane. >> >> Bob Nuckolls, who is an expert on electrical systems in airplanes, has an >> article on Lithium iron-phosphate batteries in the latest Kitplanes, >> entitled "Battery facts and fables: lithium lead-acid equivalency. It >> starts on page 63 of the September 2014 issue. >> >> At this point, he doesn't endorse Lithium batteries, mostly because of the >> lack of information that manufacturers have provided to him. He also delves >> into the special issues that a person using a lithium battery might >> encounter with their use. Those don't seem to be addressed by >> manufacturers. He is promising follow up articles. >> >> I found it interesting reading. >> >> Dan Branstrom >> >> _______________________________________________ >> Search the KRnet Archives at http://tugantek.com/archmailv2-kr/search. >> To UNsubscribe from KRnet, send a message to KRnet-leave at list.krnet.org >> please see other KRnet info at http://www.krnet.org/info.html >> see http://list.krnet.org/mailman/listinfo/krnet_list.krnet.org to change >> options >> > > ------------------------------ > > Subject: Digest Footer > > _______________________________________________ > See KRnet list details at http://www.krnet.org/instructions.html > KRnet mailing list > KRnet at list.krnet.org > http://list.krnet.org/mailman/listinfo/krnet_list.krnet.org > > > ------------------------------ > > End of KRnet Digest, Vol 2, Issue 194 > ************************************* -- Please do not forward this email without deleting the email address of the sender. Please do not forward any emails without using the Bcc option (Blind carbon copy). If you just use the forwarding option, internet spammers and crooks can ?catch? all the email addresses and send your friends and family messages that appear to be from you.