Back on skis!

[kestrel]

This past Monday, Dave converted the plane back to skis for the winter. I also recently installed an EarthX ETX900 Lithium battery. 5 pounds and cranks the O-540 better than the Odyssey PC680 did.

[SpainCub]

Beautiful airplane and scenery! Great way to enjoy the season!

Happy holidays!

[Battson]

Great to hear the EarthX battery is working well with the -540. How old was the PC680 which it replaced?

I am finding my PC680 is getting a little tired after 3 years / 500hrs of engine starts. I wonder whether its on the way out.... I also wonder whether a new PC680 would be the same as / better / worse than an EarthX900.

[Flygirl1]

Is your Battery on the firewall or inside under the seat? D.

[kestrel]

Great to hear the EarthX battery is working well with the -540. How old was the PC680 which it replaced?

I am finding my PC680 is getting a little tired after 3 years / 500hrs of engine starts. I wonder whether its on the way out.... I also wonder whether a new PC680 would be the same as / better / worse than an EarthX900.

The most PC680 was just under 1 year old. Perhaps 50-60 hours of use? It was still working "well" and had been treated well. The EarthX-900 is definitely producing a somewhat snappier start.

That is the 3rd PC680 in the airplane since I bought it ~350 hrs ago. I had had some problems with cold weather starts, no primer, and eventually a mag that needed overhaul. The consequence is that I had done a number of deep cycle discharges followed by a jump start on the previous batteries. They had very short lives. The Odysseys are supposed to be good for deep cycle. They may be better than "standard", but I would not recommend them for deep cycle use. I used them in a Formula Ford without an alternator. In that use, they lasted only a year or so.

I still want to see how well it works when the battery is cold. I'm not too concerned because I don't like to start with a very cold engine anyway, but still...

[kestrel]

Is your Battery on the firewall or inside under the seat? D.

It is on the engine side of the firewall. The battery is limited to 140 F and that was/is a concern. Before installing the battery, I put some stickers on the battery box that indicate the highest temperature the sticker has seen. They have not indicated much over 100 F, including a flight to GA where temps were in the low 80's. After installing the battery, I also dropped a WeatherHawk MyBlue-T Bluetooth thermometer into the box with it. So far, so good. ...but I will still be concerned when the weather warms up.

If I see temps that are too high, I will either install a heat shield and/or cold air blast tube from the baffling to it. ...or mount it on the cabin side of the firewall as I had originally intended. Keep in mind that this batter is less than 5 lbs which opens up alternate mounting methods that can't be used for a 15 lb Odyssey or 25 lb conventional battery.

[Flygirl1]

Thank you for all the info. Dennis and i have the Odessy installed on the firewall and are always looking for these kind of weight reductions. We saw the lithium a while back, but were concerned about the heat issues. Our Odessy's are new so we'll use them for now, but please keep us posted on how this one works for you. D. P.S. Have a riot on those skis!!

[Battson]

The most PC680 was just under 1 year old. Perhaps 50-60 hours of use? It was still working "well" and had been treated well. The EarthX-900 is definitely producing a somewhat snappier start.

That is the 3rd PC680 in the airplane since I bought it ~350 hrs ago. I had had some problems with cold weather starts, no primer, and eventually a mag that needed overhaul. The consequence is that I had done a number of deep cycle discharges followed by a jump start on the previous batteries. They had very short lives. The Odysseys are supposed to be good for deep cycle. They may be better than "standard", but I would not recommend them for deep cycle use. I used them in a Formula Ford without an alternator. In that use, they lasted only a year or so.

I still want to see how well it works when the battery is cold. I'm not too concerned because I don't like to start with a very cold engine anyway, but still...

Great information - thanks very much.

Please do let us know how that battery works for you in the longer term. I would be interested to know how it performs in the cold, and how long it lasts before the snappiness goes away. If you felt like reporting back in 12 months, that would be really helpful! Hopefully you get several years of use from it, but please let us know if not. My next battery will likely be the same as yours, if it works well for you.

I presume that because it's a Li battery, it will not tolerate deep cycles or being drained below 60% voltage?

[bearhawk2015]

I am on my 2nd pc680 battery using it to start my 540. The first one lasted 1 1/2 years and the second one is going on a year and half also. When the first one quit I wanted to put in an earthx but I wanted to fly right away and not wait for it to ship so I went to batteries plus and got a new pc680. When this one craps out I'm going with the earthx. No more pc680 for me.

[JimParker256]

The EarthX batteries are gaining a lot of popularity with the Alaska / Idaho / Wyoming folks on the BackCountry Pilots and SuperCubs forums. They apparently do need to be "warmed up" a bit on super cold days before cranking the engine. Some guys reported that the first couple of tries would barely move the prop at all, but then all of a sudden it cranked like crazy. Supposedly, you can just turn on your lights for a few minutes, and that load will self-warm the battery to where it will easily crank the engine on the first try, and several of the guys report this is now their SOP for cold weather - Lights ON, preflight, then Lights OFF to crank engine. Of course, with everyone also going to LEDs for lighting, I guess we'll have to eventually figure out another way to warm them up!

[kestrel]

Please do let us know how that battery works for you in the longer term.

There might be a write-up on it when I feel I know something. ;-)

I presume that because it's a Li battery, it will not tolerate deep cycles or being drained below 60% voltage?

It is a Lithium Iron Phosphate (LiFePo) which is not the same chemistry in your cell phone, electric RC or Boeing 777. Key is that they are much more stable. I hear you can drive a nail through them and they won't catch fire. They still have limits, but much safer than the more common Lithium chemistries. That said, I've had a hard time finding good data on what charge/discharge levels bother them.

[kestrel]

I guess we'll have to eventually figure out another way to warm them up!

I'm thinking something like one of these in the battery box with a switch on the panel is the way to go. It puts all the warmth in with the battery:

https://www.amazon.com/Dorman-628-040-Universal-Seat-Heater/dp/B002U6IL9O

...but it might not be needed. I've read that giving the starter a short crank and then waiting a minute can work also.

[kestrel]

...or this one which is cheaper?

https://www.amazon.com/Crimestopper-HSK150-Deluxe-Heated-Seat/dp/B001L6HYQK/ref=pd_cp_263_2?_encoding=UTF8

[JimParker256]

Yeah, I went back, and that's what the guys with LED lights are doing. Hit the starter for a very short time, wait a bit, and then crank away. Seems to warm .em right up. But keep I. Mind, the EarthX is a very advanced battery, and they provide some very specific guidance about which models to use with which type aircraft, the maximum voltages for charging, etc. Used correctly within their guidelines, people are having great success with them. Use the wrong battery, charge it at too high of a voltage level, or otherwise ignore their research and recommendations, and you'll destroy it in no time flat. I've followed up on some of the so-called "horror stories" people refer to, and in every case I could find actual facts about, the failure were caused by ignoring the company's recommendations. I'm sold on 'em.

[Battson]

There might be a write-up on it when I feel I know something. ;-)

It is a Lithium Iron Phosphate (LiFePo) which is not the same chemistry in your cell phone, electric RC or Boeing 777. Key is that they are much more stable. I hear you can drive a nail through them and they won't catch fire. They still have limits, but much safer than the more common Lithium chemistries. That said, I've had a hard time finding good data on what charge/discharge levels bother them.

I was thinking more about caring for the cells, but yes I looked into their chemistry and they are a safe option.

[kestrel]

Got out on skis a couple of weeks ago.





Emilie logged her first ski time: