Need help choosing a battery

The LiFePO4 batteries that are configured for starting are epic good. I don't know how it would compare in your situation, he uses it to start a 540 cubic inch Lycoming aircraft engine. It will crank and crank seemingly forever. Those engines when hot can be difficult on the best days. They tend to draw quite a bit more than car engines and are tough on batteries.

The BMS on many of these LiFePO4 batteries are not designed for high amp draw. But on the ones that are, they work exceptionally well. Also, the BMS will reset in a few seconds on some models. Others the BMS 'latches" and it may take a pair of jumper cables to bring it back.

A starter for a 460 ford is the same size motor as my 12,000lb winch, so that tells me a little something.

So how do you tell what the BMS is designed for? Is it just a gamble?
 
So how do you tell what the BMS is designed for? Is it just a gamble?
It's in the specs. Continuous Amp draw and 30 second ratings along with BMS reset time. You could accurately measure draw and determine which one would work for you.

I provided one battery example, but there are quite a few choices. But as you mentioned, a winch can be a power consuming monster, and a U1 sized battery may not be ideal.
 
It's in the specs. Continuous Amp draw and 30 second ratings along with BMS reset time. You could accurately measure draw and determine which one would work for you.

I provided one battery example, but there are quite a few choices. But as you mentioned, a winch can be a power consuming monster, and a U1 sized battery may not be ideal.

I emailed a guy that works at Antigravity batteries and seemed like he guided me away from lithium because of the BMS. Then you tell me lithium will relentlessly power a starter for a 540 cubic inch engine which is the equivalent to a 12,000lb winch, so I don't know what to think anymore.

My winch is 5000lb and it struggles to lift 1500lbs so I doubt my batteries and alternator will power it fully. No way they could power a 12,000lb winch, especially without even having an alternator helping. If what you say is true then that lithium is doing 10x more than my 2 batteries and alternator could dream about.

Do you think an ATV with two U1 flooded batteries could start that 540 engine?
 
I think 2 fresh U1 batteries of high quality will start an IO-540. In fact, there are U1 batteries that are used in aircraft. They are not cheap. I used the $420 (about U1 sized) Concorde RG-25xc (350cca) on our IO540 powered stunt plane. It was mounted in the cabin, but very near the engine (no heat), with very large wiring. Had to change it every year. Otherwise you'd get stranded.

This one is a fairly high quality U1. It is NOT good enough for a big Lycoming, $163:

https://www.aircraftspruce.com/catalog/elpages/gellcellbatt.php

The Concorde RG 25xc. It is good enough to crank the IO540, but only for a year. Specialized, high count internal plates:

RG-25XCA.jpg


Here is a much lighter LiFePO4 battery cranking a similar engine, hint, much better!



The EA300L stunt plane I used the Concorde battery in:

CZGPj89.jpg
 
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I think 2 fresh U1 batteries of high quality will start an IO-540. In fact, there are U1 batteries that are used in aircraft. They are not cheap. I used the $420 (about U1 sized) Concorde RG-25xc (350cca) on our IO540 powered stunt plane. It was mounted in the cabin, but very near the engine (no heat), with very large wiring. Had to change it every year. Otherwise you'd get stranded.

Interesting.

About a dozen years ago or so I was interested in the most efficient winch because I'd camp in a spot where I needed to lower a trailer down a 200ft hill and then winch it back up with a battery with a single charge that lasted all weekend.

So I rigged up a test with 3 winches: a 2000lb, 5000lb, and 12,000lb with 200ft of cable pulling a train of 3 atvs with the brakes locked up a shallow hill, but I used a big deep cycle marine battery from autozone instead of a U1.

The 5000lb pulled it with plenty of battery power to spare and that's the winch I ended up using. The 2000 was underpowered and struggled too much to work very efficiently, but the worst of all was the 12,000lb which couldn't even make a full pull. I can't remember how far it did pull, but it was embarrassingly short. The 12,000lb wastes gobs of power in the gearing and probably in the massive motor as well.

The video you posted the starter was under a fair load for 8 seconds and I'm wondering how long it could keep that up. Dumping a load of dirt probably takes 30 seconds at least. And reeling in 200ft of cable takes a LONG time.

My experiment was based off a big deep cycle marine, so it seems like a cheap U1 SLI wouldn't get far off the starting line. I've never owned an expensive U1 so I can't say but seems hard to imagine it's much better than a big heavy deep cycle marine, but if it could crank that 540 engine for a good 30 seconds I'd say that's a heck of a testimony!

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At least one of these starters is a 460 ford. So a 12,000lb winch is basically a 460 starter mounted to planetaries.

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Ha, I have a much more clear picture now. Your winch is asked to do some serious work.

I think you need something along the lines of the Turkey Point nuclear power plant to winch a camp trailer 200 feet up a hill.

All kidding aside, the (actual and truthful) AH rating of a battery will come into play when you are asking a battery to perform real work. These things can be calculated by knowing the average amp draw of the winch, how long it is used for, how many times it's used and so on.
 
Ha, I have a much more clear picture now. Your winch is asked to do some serious work.

I think you need something along the lines of the Turkey Point nuclear power plant to winch a camp trailer 200 feet up a hill.

All kidding aside, the (actual and truthful) AH rating of a battery will come into play when you are asking a battery to perform real work. These things can be calculated by knowing the average amp draw of the winch, how long it is used for, how many times it's used and so on.

Yep I've destroyed a few winches over the years and many batteries doing serious work lol

Sounds like I need to buy an ammeter so I know exactly how many amps the winch is drawing.

I think either way I'm ruling out AGM because my charging system is set up for conventional. And although I have a beefy regulator and you said magnetos tend to be robust, I really don't want to find the extents of that robustness. If nothing else, the magneto would be contributing more heat to the engine which is already hot from being higher compression and air-cooled with poor airflow. AGM's lower resistance and faster charge rate would just add to that heat. That's especially true if I parallel 2 AGM batteries.

With lithium I still feel like I'm gambling and venturing into the unknown. Rick's motorsports electrics sells lithium kits with regulators that limit the voltage to 14.4, which is lower than 14.6 for AGM and 14.7 for conventional, so I'm guessing lithium also has a very low resistance and fast charge rate. And although lithium can turn over a 540 engine for 8 seconds, I don't know if it can do it for 30 seconds.

So I think I'm pretty much confined to the archaic flooded system until lithium tech progresses. The only question left is whether it's worth it to buy an expensive one or keep buying the cheap ones and considering them disposable. For the cost of a $300 fancy battery I could get 10 Walmart batteries.

I'd be more apt to buy an expensive flooded if it weren't for the vibration and shock issue. Although $80 for an Interstate SP40 with reserve capacity of 38 and 350 CCA isn't too expensive. For comparison Walmart's $30 battery is 230 CCA and probably 20 RC. Walmart has a 340 CCA for $50 that doesn't seem too different from the Interstate. The $50 one is 1.57lbs heavier than the $30 one, so that must mean more lead.

Maybe that's the way I'll go unless you have some other ideas. Thanks for making this a very productive thread!
 
And although lithium can turn over a 540 engine for 8 seconds, I don't know if it can do it for 30 seconds.
Absolutely it can. Our injected engines flood when sitting after a flight, due to the very high temps boiling off the fuel in the lines. This makes starting difficult as there is a flooded engine which tends to cough and run for a second, then get nothing but vapor from the lines for some time.

A true 30AH battery at the 1 hour rate, when new, will crank a Lycoming for about 4 minutes. With a bit of rest between 30 second crank cycles. The 60AH Lithium that has the same weight will crank it twice as long and faster too. But again, the battery choice is important.
 
Absolutely it can. Our injected engines flood when sitting after a flight, due to the very high temps boiling off the fuel in the lines. This makes starting difficult as there is a flooded engine which tends to cough and run for a second, then get nothing but vapor from the lines for some time.

A true 30AH battery at the 1 hour rate, when new, will crank a Lycoming for about 4 minutes. With a bit of rest between 30 second crank cycles. The 60AH Lithium that has the same weight will crank it twice as long and faster too. But again, the battery choice is important.

How long has he or you been using the lithium battery? Did you or he make changes to the charging system?

I was a little wrong about Rick's. They set the charging voltage to 14v for lithium.

***This kit is not for use with standard lead acid batteries. The voltage set point is 14V +/- .2. Please contact the manufacturer of your Lithium Ion Battery to ensure our product has the correct set point for their product. **** https://ricksmotorsportelectrics.com/New-Honda-Charging-Kit-Lithium-Compatible-14_99_101

And here are some reviews from the link you sent me of the lithium battery your friend bought. I really don't want to have to send a battery back. Also don't want to fight with a BMS.

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I emailed a guy that works at Antigravity batteries and seemed like he guided me away from lithium because of the BMS. Then you tell me lithium will relentlessly power a starter for a 540 cubic inch engine which is the equivalent to a 12,000lb winch, so I don't know what to think anymore.

My winch is 5000lb and it struggles to lift 1500lbs so I doubt my batteries and alternator will power it fully. No way they could power a 12,000lb winch, especially without even having an alternator helping. If what you say is true then that lithium is doing 10x more than my 2 batteries and alternator could dream about.

Do you think an ATV with two U1 flooded batteries could start that 540 engine?
Winches are rated based on pulling power from the inner most wrap.
So if you have 3 wraps of line on your winch that's probably cutting the pulling power in half.
That's why I only load about half the length of cable a winch can hold in in my winches at most. My little winch will hold 50' of 5/16 inch cable. Yeah it maybe has 20 feet in it. I can add length easy.
I may need maximum pulling power from a tree 10' feet away. Can't do that quickly or easily with 50' on the drum.
 
You were given the answer by @fantastic above. V=IR. If voltage increases with constant resistance current drops.

They don't charge correctly at a Lead acid voltage, and its not constant - it has a profile, depending on where in the charge cycle it is I believe the higher voltage has something to do with the electrolyte, but I am not sure - I am not a chemist.

Why do you think high quality battery chargers have different settings for lead acid and AGM?

Anyway, a regular charger will get you to about 80% charge +/-. Maybe that is high enough. Are you sure your current batteries are failing from low charge? Might be failing from vibration?
The Battery Minder charger I have says to use the AGM charge cycle only for Optima, Northstar and Odyssey. The plain AGMs use the normal flooded cycle.
 
Winches are rated based on pulling power from the inner most wrap.
So if you have 3 wraps of line on your winch that's probably cutting the pulling power in half.
That's why I only load about half the length of cable a winch can hold in in my winches at most. My little winch will hold 50' of 5/16 inch cable. Yeah it maybe has 20 feet in it. I can add length easy.
I may need maximum pulling power from a tree 10' feet away. Can't do that quickly or easily with 50' on the drum.

The winch on my dump trailer only has 15-20 feet of cable. The only reason it's that long is so I can cut some off when it gets too frayed. I can't use all of the 1st wrap because the cable would pull out of the hole in the drum, so I start with half the first wrap and end up overlapping quite a bit.

But winches on my rides always have the maximum length I can fit on the drum and I usually go down a cable size so I can fit more length. I don't need much pulling power and mostly I need length to find the nearest tree that's straight ahead or to pull a full length of a hill. I also use winches to pull trees down so I like to be farther than the tree is tall.

But if pulling power is a concern then it's real easy to add a snatch block. I leave a snatch block dangling on the end of my cable anyway because I tend to use them a lot. When I wrap around a tree I hook the hook to the snatch block instead of the cable so I don't get a kink in the cable.
 
The Battery Minder charger I have says to use the AGM charge cycle only for Optima, Northstar and Odyssey. The plain AGMs use the normal flooded cycle.

Mine just says AGM. Are you sure they aren't saying Optima, etc as an example? Seems weird they would say do not use AGM on AGM batteries unless they are Optima, etc.

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Mine just says AGM. Are you sure they aren't saying Optima, etc as an example? Seems weird they would say do not use AGM on AGM batteries unless they are Optima, etc.

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Normal flooded settings are close enough. Main thing you don't want is a long equalization cycle for a flooded deep cycle used on an AGM. You won't have that happen unless you have a "flooded deep cycle setting" on your charger. Few chargers have this.
Most digital battery chargers have a flooded, AGM and GEL setting.
The Gel setting is also good for lithiums.
 
Normal flooded settings are close enough. Main thing you don't want is a long equalization cycle for a flooded deep cycle used on an AGM. You won't have that happen unless you have a "flooded deep cycle setting" on your charger. Few chargers have this.
Most digital battery chargers have a flooded, AGM and GEL setting.
The Gel setting is also good for lithiums.

It defaults to gel when it starts and in the manual it says it's because gel is the most picky so that's the default setting. It's ok to use gel setting on AGM and flooded but not the other way around. Although I think the flooded setting would work ok on AGM, I think the main issue could be that it's not good for the charger since AGM has less resistance and would draw more amps from the charger.
 
It defaults to gel when it starts and in the manual it says it's because gel is the most picky so that's the default setting. It's ok to use gel setting on AGM and flooded but not the other way around. Although I think the flooded setting would work ok on AGM, I think the main issue could be that it's not good for the charger since AGM has less resistance and would draw more amps from the charger.
Gel batteries die if they get bubbles.
 
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