Hi, We have 2 litium batteries. I made steel boxes around them, this seals the fire. I made also thermocouples in them so if one getteing hot I switch this one off. And using the backup batterie. The fire is safe in the box. One box including batterie is 1600 gram. Somis save a lot off weight. See my boxes below. http://www.masttotaalconcept.nl/kr2/styled-28/index.html
Stef > Op 13 januari 2020 om 17:12 schreef Jeff Scott via KRnet > <krnet@list.krnet.org>: > > > What's special about the EarthX Battery for Aviation (ETX-680C)? > > I think everyone knows about all the issues with Lithium batteries and fires, > which has a lot of people afraid of Lithium batteries, even though everyone > is carrying one in their pocket installed in their phones. So what's > different about the EarthX Aviation battery? First off, all Lithium > batteries provide a very high energy release, so can provide a lot of > amperage all at once from a very small, light weight package. However, there > are a number of Chemical processes to make a Lithium battery. Lithium-ion > Polymer batteries (LiPo) are the ones that are famous for catastrophic > failure under either heat or impact with spectacular fires. The EarthX > batteries are a Lithium Iron Phosphate (LiFePO4) composition, so are not > prone to burning upon break down. So instant and catastrophic fire is not a > concern with them. Most of the Lithium batteries being sold for automotive > use are Lithium-Iron (LiFePO4) batteries. A 12V Lithium battery only has 4 > cells that provide 3.3 volts per cell. That is significantly different from > a wet cell battery. It is critically important for the cells in any Lithium > battery to both discharge and charge in sync with each other and always stay > balanced. It is also critically important that the cells not be allowed to > fully discharge or overcharge as that will damage the cells. So the EarthX > batteries have a Battery Management System (BMS) built into each battery. > The Battery Management System (BMS) ensures that the cells discharge and > charge at exactly the same rate and keeps the cells balanced during recharge. > The Battery management system will also disconnect the cells from the system > if the battery voltage drops below something like 9 volts or over 15.5 volts > to protect the cells from excessive discharge or a runaway charge. I've left > the master switch on after working on some avionics and discharged mine. The > BMS simply disconnects the cells and leaves everything dead. You apply 12V > to the battery for 5 seconds, and the BMS will reconnect the cells and it is > ready to go again. Additionally, the BMS adds protection to disconnect in > the case of a dead short. > > But the BMS also adds a failure point to the battery. So, EarthX added a > redundant Battery Management System to their Aviation batteries. In addition > to the second BMS, they also have installed a LED on the top of the battery > and a small wire leading from the battery. The LED will start flashing if > there is an issue with either the battery or the primary battery management > system, and the secondary battery management system will take over. The wire > can be connected to either an LED on your panel, or to an EFIS as an input > for notification of a battery management issue (I have done neither). If you > ever see a BMS issue such as a primary BMS failure, EarthX will replace the > battery. The EarthX Batteries are designed for an 8 year life span. > > I had not planned to use an EarthX battery in my KR. Since the day it was > new I have used a very standard 12V motorcycle battery that was rated at 175 > cold cranking amps, mounted in front of the firewall, and have always got a 7 > - 8 year life out of these wet cell batteries. The Odyssey battery didn't > exist when I was building my KR, and I would have switched to it, except that > it was too tall to fit in the battery box I had built for the old wet cell > batteries. However, after installing the higher compression pistons in my > engine, I kept destroying the clutch in the Niagara starter drive on the old > Delco pull starter. At $320 a pop, I decided it was time to upgrade > starters. I found a guy that was removing the B&C starter and Plane Power > Alternator from a C-85 that was going onto his Cub, so bought the whole > charging/starting system. After installing the B&C starter, I rolled the > plane out to start and the engine spun over like it was idling. Only problem > was that it wouldn't start. It's a long story, but what I found was that the > highly efficient B&C starter was so efficient that it was pulling the battery > voltage down low enough that the Emags (which require battery voltage for > starting) would not fire. My only choice at this point in time was to buy a > battery with more cranking amps. I really didn't want to install a larger > battery as I didn't have room and really didn't want to add more weight to > the plane. That left a Lithium battery as the only viable choice. So, I > studied the Lithium batteries and talked to some people that had them. I > found the EarthX battery to be the most reasonable choice for my application. > (YB-16 motorcycle battery = 175 CCA for starting, Odyssey PC680 = 170 CCA, > EarthX ETX680C = 320 CCA) I had to add a bolster under the battery and > padding around it to use the same space I had for the old wet cell battery. > I also provided a cooling air line to it, although it shouldn't need it. > With replacing the alternator and starter, I removed 10# from in front of the > firewall. With the installation of the EarthX battery, I removed another > 10#, to make for a 20# weight loss for the plane. I am coming up on 4 years > into the expected 8 year life of the battery. So far, I have been quite > happy with it. However, these batteries are not cheap at $370 per unit. > > One caveat to using a Lithium type battery. These batteries can deliver a > ton of power all at once. But they also want all that power back at once as > well. What that means is that your charging system will charge full bore > after starting until the battery is back to 100% charge, then will quickly > drop back to normal. Typically, my battery is topped off again before I even > make it to the end of he runway for run up. But if you have a low battery, > it's going to charge full bore for a bit, so you want to make sure all your > alternator wiring is up to snuff. > > There is nothing wrong with using the Odyssey battery. That's what I have in > my SuperCub Clone and have been pleased with the performance. However, if I > were to switch that plane to duel Emags, I would also need to switch to the > lighter, more powerful battery for it as well. > > -Jeff Scott > Arkansas Ozarks > > > > > Sent: Monday, January 13, 2020 at 5:47 AM > > From: "n357cj via KRnet" <krnet@list.krnet.org> > > To: KRnet <krnet@list.krnet.org> > > Cc: n357cj <n35...@ptd.net> > > Subject: Re: KR> Odyssey PC680 > > > > > > Jeff/All, > > I did get a new battery but stayed with the conventional that I had for > > now. I did talk to the battery guys and they told me that the company that > > I am using as well as some others have the lithium in matching sizes to > > what they produce for the conventional batteries. SO to do a bit more > > homework I am wondering about Jeff's statement below about configuring to > > aviation use. What specifically are the things that need to be in the > > battery to make it safe for flight? > > I remember a couple or maybe a few years ago someone had posted a pretty > > long description of the things that are wrong with the lithium's which just > > made it seem like they were not ready for our use yet, but technology has a > > way of getting things worked out. If I remember correctly the charging > > system was also part of the issues to configure correctly for the > > lithium's.? > > Thanks, > > Joe Horton, N357CJ > > > > ----- Original Message ---- > > > > Subject: Re: KR> Odyssey PC680 > > > > Thanks again Jeff, > > I am going to look into this battery. > > Joe Horton > > ----- Original Message ----- > > > > Cc: "Jeff Scott" <jscott.pla...@gmx.com> > > EarthX has done a good job of configuring this battery specifically for > > aviation use. > > > > -Jeff Scott > > Arkansas Ozarks > > > > > > _ > > > > _______________________________________________ > > Search the KRnet Archives at > > https://www.mail-archive.com/krnet@list.krnet.org/. > > Please see LIST RULES and KRnet info at http://www.krnet.org/info.html. > > see http://list.krnet.org/mailman/listinfo/krnet_list.krnet.org to change > > options. > > To UNsubscribe from KRnet, send a message to krnet-le...@list.krnet.org > > > > _______________________________________________ > Search the KRnet Archives at > https://www.mail-archive.com/krnet@list.krnet.org/. > Please see LIST RULES and KRnet info at http://www.krnet.org/info.html. > see http://list.krnet.org/mailman/listinfo/krnet_list.krnet.org to change > options. > To UNsubscribe from KRnet, send a message to krnet-le...@list.krnet.org Steph and his dad are building the KR-2S see [http://www.masttotaalconcept.nl/kr2](http://www.masttotaalconcept.nl/kr2) _______________________________________________ Search the KRnet Archives at https://www.mail-archive.com/krnet@list.krnet.org/. Please see LIST RULES and KRnet info at http://www.krnet.org/info.html. see http://list.krnet.org/mailman/listinfo/krnet_list.krnet.org to change options. To UNsubscribe from KRnet, send a message to krnet-le...@list.krnet.org
