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Lithium starting battery for boat iam so confused!

JP24DUCKS

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Chenoa,IL
So iam looking at installing a dakota lithium starting battery in a bass boat with a 1999 mercury 225 pro xs motor. Can I just drop in or do I need to add things in for it? For example dc to DC charger or isolators or alternator protection module. Thanks for any advice
 
Unless you like being dead in the water, I wouldn’t do it. If it’s always near full charge you would never see a problem. However, say you’re running the depth sounder/fish finder and some tunes for a while. Now you start the engine and the alternator is going be working really hard because lithium pulls many times the load than a lead acid. Yes that 225 has a big alternator for an outboard but it just isn’t going to handle that duty cycle. Yes you could rig up a DC/DC charge control but you would need to do some wiring surgery to separate the starter circuit from the running/charging circuit. If you are having problems replacing batteries frequently and that’s why you want lithium. I would suggest that you stick with lead batteries and buy a good disconnect switch at the battery to eliminate parasitic discharge and/or a “Battery Tender”. Keep it simple, so you’re on the water and moving. Lithium is great for trolling batteries BUT you need a charge controller IF you are planning on the engine to slowly build them back and not just shore power.
 
Unless you like being dead in the water, I wouldn’t do it. If it’s always near full charge you would never see a problem. However, say you’re running the depth sounder/fish finder and some tunes for a while. Now you start the engine and the alternator is going be working really hard because lithium pulls many times the load than a lead acid. Yes that 225 has a big alternator for an outboard but it just isn’t going to handle that duty cycle. Yes you could rig up a DC/DC charge control but you would need to do some wiring surgery to separate the starter circuit from the running/charging circuit. If you are having problems replacing batteries frequently and that’s why you want lithium. I would suggest that you stick with lead batteries and buy a good disconnect switch at the battery to eliminate parasitic discharge and/or a “Battery Tender”. Keep it simple, so you’re on the water and moving. Lithium is great for trolling batteries BUT you need a charge controller IF you are planning on the engine to slowly build them back and not just shore power.
The dakota battery has 1000 CCA where my motor only requires a 950 cca. Dakota says it is a drop in replacement limited to an 80 amp alternator my engine has a 60 amp. The battery has a bms protection from overcharging that will cutoff at 15 volts
 
Ask a boating forum about it. Don’t be a beta tester. I love lithium, but it’s my absolute last choice for a starting battery. Mercury has OK’d it on some of their newer models BUT “condition must be met”. Invest the money in trolling batteries or towards a new Benelli.
 
Ask a boating forum about it. Don’t be a beta tester. I love lithium, but it’s my absolute last choice for a starting battery. Mercury has OK’d it on some of their newer models BUT “condition must be met”. Invest the money in trolling batteries or towards a new Benelli.
I ended up calling mercury and they don't recommend it for older motors. Trolling motor batteries are next and I already have a h&k benelli and a sbe2
 
Hi there !
I've confused ? with Dakota starting battery datasheet! they mentioned in their datasheet that it has 1000 CCA ( cold cranking amper) for "DAKOTA LITHIUM DL+ 12V 60Ah BATTERY" but also it mentioned that maximum discharge current is 750A for only two seconds pulse! as I knew CCA is defined as " measures the number of amps produced by a charged battery over 30 seconds at zero degrees Fahrenheit without dropping below 7.2 volts." so how it can deliver 1000 CCA but only 750A for only two seconds!
 
Hi there !
I've confused ? with Dakota starting battery datasheet! they mentioned in their datasheet that it has 1000 CCA ( cold cranking amper) for "DAKOTA LITHIUM DL+ 12V 60Ah BATTERY" but also it mentioned that maximum discharge current is 750A for only two seconds pulse! as I knew CCA is defined as " measures the number of amps produced by a charged battery over 30 seconds at zero degrees Fahrenheit without dropping below 7.2 volts." so how it can deliver 1000 CCA but only 750A for only two seconds!
There is no way to do a CCA test on a lithium battery.
It's sales marketing speak "Lithium battery equivalent to 1,000 Cold Cranking Amps (CCA) of lead acid battery".
Some slick marketing guy with a calculator got a big bonus for that one :)
They also recommend using a DC-DC charger when using it in an auto/marine unless specific conditions are met.
You also get a free lithium charger on anything over 54Ah.
 
You’re running into this ugly ‘equivalency’ business that sometimes plagues a type of product when the technology changes. Same as tires having ‘ply ratings’ which is not their actual ply count, or electric vehicles having ‘mpg-e’. Just clunky business we must navigate.

So the current that a bms will shut off over is time dependent. At some super high number it will trip almost instantly, at some lower current it will last 1-5 seconds, at some lower current than that it will sustain continuously it until the battery is drained.

So on principle i agree that a battery should not be rated using the ‘CCA’ rating unless it could hit the actual test conditions that that refers to, but technically a lifepo4 couldnt at all because i believe that test refers to the number of amps a battery can hit without dropping to 7.2 volts (the rest of the voltage being converted internally to heat due to the battery’s internal resistance), and a lifepo4 BMS would stop the test at ~10.0v.

So yeah, annoying but also something we must ‘deal with’ because better rating systems for lifepo4 as starter batteries have not been widely accepted. I can tell you that a lifepo4 will drop much less voltage internally and ‘act’ like a much bigger lead acid if you are comparing say 100ah to 100ah. For example, when i do a 100amp load test on a 100ah i am using as a starter battery, the voltage only sags to the region marked ~1100cca on the ‘cheat sheet’ of color coded regions on the analog voltage gauge of the tester. I have never seen an actual lead acid starter battery (up to group 94 or 31 size anyway) test that high on that little tool.

Any decently sized lifepo4 with a sufficiently large BMS (750a for 2 seconds is huge) will perform extremely well as a starter battery.
 
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Voltage and alternator related too. Check with motor manufacturer . Some do not recommend.
 
So you meant that they used equivalent lead acid battery cca rating in comparison! Anyhow does anybody know the cell that Dakota used in their starter series battery? it seems that their lifepo4 battery cells have high C rate higher than 10C, at which a 60 Ah cells can deliver near 800 A ! (at least as Dakota datasheet says unless this is another advertised value! ) has anyone seen a teardown of their starter battery? if so please share the link . There are a lot of other brands nowadays that present lifepo4 starter battery such as Ionic, ithechworld , etc while lifepo4 batteries aren't well known for their high rate(more than 3C) and they aren't suitable for freezing weather charging and cold cranking current! so I'm really curious to know more about their battery cells and technic they used in cold weather! is it just the heating function for freezing charging or something else because I found eve lf22k with real 20C discharge rate and capability of charging in -20 degree centigrade ( also don't know how this lifepo4 cell can tolerate such a freezing ? temperature in spite of its lifepo4 type! )
 
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You actually shouldn’t use them for trolling motors either.
Why not? At least three times the run time for the same weight. No worries about running them below 50% and reducing life and not having to replace them every year or so because you did a lot. Our lithium gets approximately 18 hours of normal speed trolling time plus running fish finder and radio, leaving the starting battery for getting you home. Thou I’m very reluctant to use lithium for starting batteries, trolling is a place where they shine. If you plan on charging the trolling battery from the engine, you should use an appropriate sized DC to DC charge controller to reduce current draw and protect the engine’s alternator. We just plug into 45 amp charger in the garage and it’s ready to go again before we are.
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They’re not designed to be ran with that steady of voltage/ amperage for a long period of time. With a lead acid/ agm, voltage drops off.

New ones are starting to be revamped for lithium.
 
A lot of engines are the same way. If I am troubleshooting one for electrical issues, the first thing you do is eliminate the lithium battery. And it is most of the time the culprit.
 
We run 10 to 13 amps for normal trolling. The motor will max amp at 40 amps. The speed, surge current and continuous current both types of chemistry are exactly the same at least for the first hour. If the speed control or motor didn’t thermally max out in 15 minutes of full power, it isn’t going to do it later. The author of the page is miss informed or wants to sell deep cycle batteries. Will the motor wear out sooner with lithium? Of course because you have more fishing time on it. But actual run time or total revolution count should be no different for the life of the motor. Chances are the motor will die of seal failure first.
 
So you meant that they used equivalent lead acid battery cca rating in comparison! Anyhow does anybody know the cell that Dakota used in their starter series battery? it seems that their lifepo4 battery cells have high C rate higher than 10C, at which a 60 Ah cells can deliver near 800 A ! (at least as Dakota datasheet says unless this is another advertised value! ) has anyone seen a teardown of their starter battery? if so please share the link . There are a lot of other brands nowadays that present lifepo4 starter battery such as Ionic, ithechworld , etc while lifepo4 batteries aren't well known for their high rate(more than 3C) and they aren't suitable for freezing weather charging and cold cranking current! so I'm really curious to know more about their battery cells and technic they used in cold weather! is it just the heating function for freezing charging or something else because I found eve lf22k with real 20C discharge rate and capability of charging in -20 degree centigrade ( also don't know how this lifepo4 cell can tolerate such a freezing ? temperature in spite of its lifepo4 type! )
I’d love see a teardown of one of those. My assumption would be a more or less common bms but with an additional discharge contactor.
 
I’d love see a teardown of one of those. My assumption would be a more or less common bms but with an additional discharge contactor.
I think they don't use contactor! instead they use BMS rated for short time high current that's why they limited time to 3, 5 or 8 seconds. Here are Daly starting battery BMS!
 

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Technology is causing marketing speak to have a heart attack. Trolling motors are rated at maximum power, not continuous power for the WOW! factor. They aren't designed to run at 100 %. Don't run it at 100%, but provide it with 100%. Heck, even the National Electric Code says max permitted load on a circuit is 80%. When marketing catches up, that 70 pound thrust motor will be a new model rated at 60 pounds continuous.
 
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