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Too good to be true? Odyssey PC680 alternative $37.49.

I am on my ninth year with the original Oddyssey battery and still cranks just as strongly as the first day. I wonder this will last nearly as long.
 
I've used low cost Battery Mart supplied batteries in the past. They cranked the engine and seemed to do OK. Have no objective evidence of lifespan of these low cost items versus the high brand loyalty items, but my recollection was a ~2 year life on the battery. And no, I didn't spontaneously combust when I used it just because it wasn't Odyssey.

I don't recall if this was the exact battery, but it's close.

http://www.batterymart.com/p-12v-18ah-sealed-lead-acid-battery-1.html
 
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Interesting... I suspect more specs are required before an assessment of suitability in the aircraft application may be carried out. Of particular importance are the battery's cranking ability, as well as the discharge and recovery curves. The specs available on their website don't appear to cover this info, unless I've totally missed them.

There are lots of small AGM batteries out there, and most "look" like a PC680. It's only when you ask them to crank a cold aircraft engine that you learn they may look like a PC680 but don't crank like a PC680.
 
I recently bought a battery on line for my Milwaukee cordless drill. A Milwaukee brand battery was about $65.00. I bought a Chinese replacement for about $25.00. It lasted about a month. I put it on the charger and it is now flat and my charger no longer works either. Can't say if it ruined the charger or the charger ruined the battery, but it does seem more than a coincidence.
 
I'm not sure $37. is worth risking a runaway to save a little $$$


What's a "runaway"? These are lead-acid batteries.

FWIW I have used a similar battery branded as a Tempest, and it lasted well, up to 4 years, when I replaced it even though it was still going strong. I think I paid about $55.

I figure you could change the battery every two years and still be ahead.

To each his own, of course.
 
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I recently bought a battery on line for my Milwaukee cordless drill. A Milwaukee brand battery was about $65.00. I bought a Chinese replacement for about $25.00. It lasted about a month. I put it on the charger and it is now flat and my charger no longer works either. Can't say if it ruined the charger or the charger ruined the battery, but it does seem more than a coincidence.

Cordless batteries aren't lead-acid batteries. I don't think this example is relevant to aircraft batteries. Wouldn't the drill batteries be NiCad's? Very different batteries.
 
I have been using a similar battery in my Jodel for 3 years. It still is in great shape and cranks well even in winter. But as with anything from the other side of the ocean it is hard to make generalizations. There are many different mfgs and you never know for sure what you are getting.
 
Drill battery

Cordless batteries aren't lead-acid batteries. I don't think this example is relevant to aircraft batteries. Wouldn't the drill batteries be NiCad's? Very different batteries.

Some NiCad
More LiOn.
 
Bryan states that he got about a ~2 year life on the battery (low cost model). My PC680 came as part of an unfinished kit. It presumably spent it's first 7.5 years on a shelf. It cranked my 0-360 strongly for a year and a half until this spring when it showed weakness. Current price for the PC680 is $106.95 or less at your door. Using a nine year lifespan, that's $11.88 a year. I gladly bought a new one.

Cheers, David
RV-6A KBTF
 
Problem is that my most recent PC680 has lasted less than 2 years (I'm on my 4th I believe in 13 yrs). Reading other reviews both on here and on Amazon, seems like the Odyssey PC680 can last upwards of 9 years in some cases and only 9 months in other cases. In that regard, it doesn't seem necessarily better than the cheaper ones.
 
PC680 Early Failures

My hangar neighbor's PC680 failed at about the two year point. He had been hooking it up to the Harbor Freight float charger that goes on sale for $4.99 after every flight and leaving it connected until the next flight. This practice was carried over from his experience with wet lead-acid batteries. I've checked a few of these float chargers, and none of them came close to the charging specifications printed right on top of the battery. He's now convinced that he ruined his battery with this charging practice.

The PC680 can sit idle for a year with no ill effects. There's no need to trickle charge in the meantime. Any charging should be done with reference to the aforementioned specs.

No connection with Odessey other than being a satisfied customer.

Cheers, David
RV-6A KBTF
 
Yeah. Cheap trickle chargers and Odysseys don't fare well. I occasionally use a sub $200 Battery Minder smart charger designed specifically for Odysseys and Concorde RG's. I got tired of cheap Harbor Freight type chargers ruining expensive batteries.

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Jim
 
Yes, too good to be true. Look at the weight, PC680 weight is 15.4 Lbs, Mighty Max is 11.9. That is 3.5 pounds lighter. Another way to look at it is that the Mighty Max is 3/4 of the weight of the PC680. I suspect the amp-hours are exaggerated. They might exaggerate the cold cranking amps too if they published them.
 
That may be true, but some of it may be case weight. My Emmy has a Powersonic 25ah in it that cranks like a mutha and it's almost 4 years old now. My ten has a 35ah UBC that cranks and holds charge well. They cost around $60 and you can buy them anywhere. Brand name SLA batteries commonly used in the "real world" are pretty consistent. I'm always dinkin with something and have a tendency to kill batteries due to stupidity, so I don't use expensive ones. I just find a brand name SLA with the correct terminals, rating, and size and use it. I never have problems until I do something to kill it. Parts is parts.
 
I've used the "cheap" batteries a few times on the RV-6 and now on the Fokker replica (Continental O-200). I found them to be very adequate for cranking an O-320 in moderate (or pre-heated) temps. The PC680 would probably be a better choice if routinely starting a Lycoming in cold climes without preheating, but for many of us the Panasonic, Powersonic, and other lesser known brands work quite well. The $40 "PC680 wannabe" in the Fokker spins the Sky-Tec starter on the O-200 as if it was a real PC680. Just don't expect to get 6-8 years of service like you might expect from an Odyssey.

And trickle charging after every flight is a no-no with any of these batteries or a PC680.
 
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OK, here is a problem!

I purchased one of these to use during construction (So I can test electrical stuff) and it does not fit in the Van's battery box. The MightyMax batter is just a little bigger! *sigh*

The vendor is being very helpful, and we are currently working out a solution to this.

For now, the PC680 replacement battery by MightyMax does not fit in the Van's firewall battery box.

I'll let you all know what happens.

CC



Anyone heard of these guys? According to the link, this is a direct replacement for the Odyssey PC-680. And that $37.49 includes free shipping (I called/verified).
https://www.mightymaxbattery.com/p3...4cBFGYy9mpVvWnH2XDEDUPJ8OlTVCC9c6lhoCLEfw_wcB
 
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Problem is that my most recent PC680 has lasted less than 2 years (I'm on my 4th I believe in 13 yrs). Reading other reviews both on here and on Amazon, seems like the Odyssey PC680 can last upwards of 9 years in some cases and only 9 months in other cases. In that regard, it doesn't seem necessarily better than the cheaper ones.
I am on my 8th year of flying and probably few months prior to flying so close to 8.5 years and still goes strong. I always have it connected to a charger despite many reports that the charger may kill it.
Needless to say, I am waiting for it to get weak so I can get a EarthX battery but so far so good.
 
Yes they are lead-acid and still vulnerable to thermal-runaway..

Gotta say, I have never heard of thermal runaway on a lead acid battery. NiCD, yes. Lead Acid, no.

I stand by to be educated, always willing to learn something new.
 
OK, here is a problem!

I purchased one of these to use during construction (So I can test electrical stuff) and it does not fit in the Van's battery box. The MightyMax batter is just a little bigger! *sigh*

The vendor is being very helpful, and we are currently working out a solution to this.

For now, the PC680 replacement battery by MightyMax does not fit in the Van's firewall battery box.

I'll let you all know what happens.

CC

Had the same issue when I bought a Tempest battery. I cut the battery box apart on two of the vertical corners, and riveted in an aluminum angle, and was able to expand the box enough to fit the new battery.
 
BUT The ad says PC680 replacement. The PC680 fits fine. and I plan to use this battery for testing and development, I may go back to a real PC 680 in the flying plane.

CC


Had the same issue when I bought a Tempest battery. I cut the battery box apart on two of the vertical corners, and riveted in an aluminum angle, and was able to expand the box enough to fit the new battery.
 
Gotta say, I have never heard of thermal runaway on a lead acid battery. NiCD, yes. Lead Acid, no.

I stand by to be educated, always willing to learn something new.

Hi Pete,

As I understand [or misunderstand] they are susceptible [albeit a lot less] than other types to runaway during charging.
 
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