LiFePo4 Lithium Start Batteries

[jimprice9]

I have a 6 cylinder Cummins that used two 12v, 290Ah, 1400 CCA paralleled AGM batteries for engine starting. I tried a pair of paralleled 12v LiFePo4 advertised to be 300Ah, 1000 CCA. They wouldn't budge the motor, just clicked at me. I suspect the BMS wouldn't allow the high discharge rate the starter demanded. Regardless, is there a LiFePo4 12v (2) or a 24v battery that packs a big enough punch to spin the starter?

 

[tiltrider1]

This topic has been discussed before. Searching "start batteries" might bring up some fairly current threads on the subject.

What was the specifications our your 300Ah LFP BMS? If it was only 250 amps then in theory you should have gotten 500 CC amps. If the starter demanded more the BMS probably shut the batteries off. In theory it would take 6 LFP batteries in parallel to produce 1500 CC amps.

That said, I really don't know what I am talking about here. Using LFP's for starting is a subject we are still trying to sort out.

 

[slowgoesit]

Try this one. I don't have any hands on experience with this, but they advertise that it is specifically designed to be a start battery:

DL+ 12V 60Ah Dual Purpose 1000CCA LiFePO4 Battery

Twoin pack, 12V 60Ah multi propose 1000 CCA lithium starting dakota battery plus for marine engine, automotive, deep cycle use. 8x longer 11year lifetime.

dakotalithium.com

 

[mvweebles]

.........or try this one. Specific for start. The 60A version has 1800 CCA, though it doesn't say for how long it can deliver that current (the one @slowgoesit linked is 750a for 2-seconds, 650a for 5-seconds).

BTW - either battery is in the 15-lb range. Tiny compared to your current setup.

H6/Group-48 Lithium Car Battery

Antigravity H6/Group-48 Hi-Power lightweight Lithium Automotive Battery with RESTART Technology. Replace lead/acid battery in Hi-Performance Cars.

antigravitybatteries.com

Peter

 

[tiltrider1]

Try this one. I don't have any hands on experience with this, but they advertise that it is specifically designed to be a start battery:

DL+ 12V 60Ah Dual Purpose 1000CCA LiFePO4 Battery

Twoin pack, 12V 60Ah multi propose 1000 CCA lithium starting dakota battery plus for marine engine, automotive, deep cycle use. 8x longer 11year lifetime.

dakotalithium.com

Specs say 2 second pulse at 750a, 5 second pulse at 500a and 100a continuous. They then say for gas engines primarily outboards.

 

[SteveK]

Specs say 2 second pulse at 750a, 5 second pulse at 500a and 100a continuous. They then say for gas engines primarily outboards.

That 1000CCA sure is misleading

 

[Marco Flamingo]

That 1000CCA sure is misleading

A lot of ad copy for LFP is misleading. Dakota may be at the forefront, but others have similar statements. The data for the Weize "starter" LFP is also a head scratcher. Its 60Ah battery states 800 Cold Cranking Amps, but the data sheet says a max of 250 Amps for 30 seconds. The stated energy (768Wh) for a 60Ah battery works out to a voltage of 12.8. That's the voltage for a fully charged lead acid. I'm skeptical of those numbers. I also don't care about CCA. That's for starting at 0 degrees Fahrenheit, like a tractor in a Duluth barn. If the batteries in your boat's bilge are at 0F, your not going anywhere because the water outside is solid. Also, as soon as you start below 0F, your alternator will deliver charge to the unheated LFP starter battery, thereby ruining it. Oooops.

Maybe I'm overly skeptical, but the fact that I can't find any "dual purpose LFP start batteries" with Bluetooth makes me wonder. Although Dakota claims to be a U.S. brand, recent teardowns have shown that to be a stretch. My suspicion is that in addition to Chinese cells they also use a Chinese BMS. That's the good part. Most of the Chinese BMSs are now available with Bluetooth and I have found that to be really interesting. With a app like Overkill, one can really see what they have purchased. Regardless of what the manufacturer says in their spec sheet, the BMS settings don't lie.

It just happened that one of my four LFP batteries had a different manufacturing date (wouldn't have known except that the Overkill app even shows that info). Although only a couple of months difference in the manufacturing date, it had a different firmware version. It had more temperature sensors (two cell sensors and one terminal sensor). It had some different settings for overcharge, overtemp, etc., etc. Not by much, but enough to see that a manufacturer (and now a purchaser) has some leeway in setting what the "specifications" are for an LFP battery. My manufacturer's website info showed a maximum current of 800A for 10 seconds for my batteries. Nowhere in any of my batteries was that specification programmed into the BMS. Overcurrent was programmed at 1020A for several seconds. While it is possible that a setting of 1020A for several seconds results in 800A for 10 seconds, because I will never ever need that, I changed it on all batteries. Bluetooth allows the user to program what they need for their application and improve the manufacturer's generic plain vanilla settings.

Short story is that whatever a starter battery manufacturer "says" its battery can do, it is the BMS that gives the actual numbers. While it would be possible to program the BMS to something the battery can't deliver, it would be interesting to see what the manufacturer believes should be delivered given their spec sheet. For some of the U.S. "made" batteries, Bluetooth would also provide information like the name of the cell and BMS manufacturer, sometimes in Hanzi characters (Manderin). Oooops.

I would love to see a starter battery with Bluetooth and see just what the BMS is actually programmed to deliver.

Mark

 

[jimprice9]

Thanks everyone for your thoughts and suggestions.
In reading your posts, carefully researching manufacture's information, following dozens of posts on multiple discussion boards, consulting several marine electricians and trying advertised "Cranking/Deep Cycle" LiFePo4 start batteries (and also struggling with a Victron/Epoch on the house side, a very long story for another thread, maybe) it is my conclusion that the Li industry does not have a product that will reliably start a large 6 cylinder 24 volt diesel engine. As the AGMs did, either deliver 1400cca for at least 5 seconds or get off the field of play! I am not willing to keep dropping 3k and confirming this conclusion ( yup, they may be returnable, what a pain shipping 100# anchors).

 

[Iggy]

Thanks everyone for your thoughts and suggestions.
In reading your posts, carefully researching manufacture's information, following dozens of posts on multiple discussion boards, consulting several marine electricians and trying advertised "Cranking/Deep Cycle" LiFePo4 start batteries (and also struggling with a Victron/Epoch on the house side, a very long story for another thread, maybe) it is my conclusion that the Li industry does not have a product that will reliably start a large 6 cylinder 24 volt diesel engine. As the AGMs did, either deliver 1400cca for at least 5 seconds or get off the field of play! I am not willing to keep dropping 3k and confirming this conclusion ( yup, they may be returnable, what a pain shipping 100# anchors).

I would have to agree with you. The next few years may have better starting Li batteries.

For what its worth. I had a 4D 1400CCA starting that was going bad. I replaced it with 2 AGM group 24s total of 1600CCA. When they die, I just might look into Li again?

 

[READY]

Maybe just go with 2x Group 31 from Costco. Not horrible to move and about $179 each?

 

[Marco Flamingo]

it is my conclusion that the Li industry does not have a product that will reliably start a large 6 cylinder 24 volt diesel engine.

I would say absolutely not true. Amperage is amperage. It is possible that a single LFP battery might not have enough amperage, just like it may not have enough voltage, i.e., a single 12V LFP won't crank a 24V starter. One would need two 12V LFP to make 24V. We all understand and accept that. Just like one might need 6 LFP to get the needed amperage to start. We aren't used to a bank of 6 batteries to start. And then one could have more than 1,500 amp hours just sitting there in the bank after starting.

That makes a bank of LFP used solely for starting seem like a waste (because it is). Larger LFP bank(s) sized for both start and house is clearly the practical usage but has not yet been accepted. But the LFP industry definately makes a product that will reliably start a large 6 cylinder 24 volt diesel engine, its just a question of how many are required.

My situation is different, having a little 4 cyl 80hp Ford Leyman. I don't know my exact starter inrush, probably somewhere around 500 amps. My four 280Ah LFP batteries are now set for 220 amps continuous and 800 amps for a few seconds (each), which is actually below the manufacturer set points. Just for a test, I fired up my engine using a single battery. It wasn't an issue, so starting with all four should not be a problem. With a bigger engine, I would need more (or bigger) LFP in the bank. I'm sure the industry makes them.

Interesting that the batteries wouldn't start but there was clicking. To me, that sounds like the BMSs didn't shut down, as there was sufficient juice to keep something clicking (likely the start solenoid). Put a multimeter on the starter cable and see what the batteries are delivering. Better might be a Bluetooth reading from the batteries.

Be suspicious of any LFP battery that has a CCA rating. What are they talking about?

Mark

 

[mvweebles]

There is a world of difference between the LFP low amperage house batteries and those such as Antigravity that are specifically made for engine start and are used in every every high compression race vehicle on the circuit (at least those that use a starter). The BMS is designed for high current discharge (up to 1500 CCA).

Lithium is very low resistance and doesn't need a deep energy reserve - 60ah is plenty. The reason diesel engines have such massive battery banks is their internal resistance requires the bulk power reservoir in order to deliver 700a of power at +12v.

LFP start batteries are still relatively expensive. But there's no reason they won't start a modest sized diesel.

Peter

 

[luna]

I'm not sure that CCA or MCA is an appropriate measure for LFP batteries.

CCA according to SAE's j537 is defined as the amount of current that a battery can deliver at 0º F. for 30 seconds without dropping below 7.2 volts.
The Marine Cranking Amp, MCA rating relaxes the test parameter from 0º to 32º F, but still 30 seconds and 7.2 volts.
Both are likely just fine for lead acid.

I find it disingenuous for a LFP battery manufacturer to state that:

.........or try this one. Specific for start. The 60A version has 1800 CCA, though it doesn't say for how long it can deliver that current

Peter

because the CCA rating itself, by definition has a time component of 30 seconds.

Further, my understanding is that a 4 cell LFP battery is 0% charged at 10 V. Despite the BMS, how does one run the cells down to 7.2 V?

 

[Delta Riverat]

Same way you run a lead acid battery down to 7.2 volt, output a lot of amps.

 

[mvweebles]

I'm not sure that CCA or MCA is an appropriate measure for LFP batteries.

CCA according to SAE's j537 is defined as the amount of current that a battery can deliver at 0º F. for 30 seconds without dropping below 7.2 volts.
The Marine Cranking Amp, MCA rating relaxes the test parameter from 0º to 32º F, but still 30 seconds and 7.2 volts.
Both are likely just fine for lead acid.

I find it disingenuous for a LFP battery manufacturer to state that:


because the CCA rating itself, by definition has a time component of 30 seconds.

Further, my understanding is that a 4 cell LFP battery is 0% charged at 10 V. Despite the BMS, how does one run the cells down to 7.2 V?

Does anyone question that definition? Does anyone really believe a 800 CCA G24 battery off a Walmart shelf for $100 would deliver 800A for 30-secs.........at 0F?

The OEMs of LFP batteries do play with terminology a bit. CA (cranking amps) being one self-defined term. I doubt a LFP battery would survive a discharge at 0F. If you're boating in those type of temperatures, an LFP start battery probably isn't a good choice, especially if you need 30-seconds of cranking to start your engine.

All I can tell you is I have a tiny LFP start battery for my 20hp OB with power tilt/start and it's the bomb. There is near zero self-discharge. I'd seriously consider one for my Perkins.

Peter

 

[Delta Riverat]

That's what I see all the time with these Lithium start batts. They talk about starting outboards. Nobody talks about starting big diesels with 20:1 compression.

I'll add that I have been using LFP's on my motorcycles for a decade and love them. I've sulfated enough LA batts by leaving too long in the garage. Never had to replace a lithium motorcycle battery. But motorcycles are pretty easy to start too.

 

[mvweebles]

That's what I see all the time with these Lithium start batts. They talk about starting outboards. Nobody talks about starting big diesels with 20:1 compression.

I'll add that I have been using LFP's on my motorcycles for a decade and love them. I've sulfated enough LA batts by leaving too long in the garage. Never had to replace a lithium motorcycle battery. But motorcycles are pretty easy to start too.

These batteries are likely used in every race car that has a starter. Maybe not 20:1 but certainly 13:1 or higher and over 700hp. But at $1k/ea, tough to be the first user.

When I talked to Antigravity about a battery for my outboard, they were mum about it and deferred back to the OEM which I get, but is quite a leap of faith. I probably could have gone with a much smaller battery which would have been nice. I suspect starting a smallish diesel wouldn't be difficult for one of their larger batteries.

Peter

 

[Marco Flamingo]

That's what I see all the time with these Lithium start batts. They talk about starting outboards. Nobody talks about starting big diesels with 20:1 compression.

That's because they are referring to a single battery when it will take a bank. OEM manufacturers don't want to get involved with custom designs. Which single LFP battery will run my house? DIY household systems have figured it out. You can't do it with one battery and, if there was one gigantic LFP battery, you probably wouldn't want it because you can do the same thing with a bank of smaller amperage batteries. Same with wanting a single LFP battery to start a big diesel. Why?

On a boat, having four or more batteries isn't usually a big deal. Given that LFP can be stacked, or on their sides, or on end, and don't need ventilation for offgassing, and don't need access to add water, they have a more flexible placement than lead. The drawback for some is that a bank large enough to crank a diesel will have extra amp hours. If one want's a one trick pony battery (start only), then LFP might not be the choice.

 

[NoRain]

All I can tell you is I have a tiny LFP start battery for my 20hp OB with power tilt/start and it's the bomb. There is near zero self-discharge. I'd seriously consider one for my Perkins.

Peter

Hi Peter, re using lithium in your dink, I’d very much like to do this, for all the obvious reasons; plus we use ours for prawning and crabbing using a trap puller. My concern was having the battery run down a tad while the pulling is going on, and then the current rush when you start back up frying the alternator in the outboard. It’s a Tohatsu 30 which has a 17.5A alternator.

 

[J.T kearney]

.........or try this one. Specific for start. The 60A version has 1800 CCA, though it doesn't say for how long it can deliver that current (the one @slowgoesit linked is 750a for 2-seconds, 650a for 5-seconds).

BTW - either battery is in the 15-lb range. Tiny compared to your current setup.

H6/Group-48 Lithium Car Battery

Antigravity H6/Group-48 Hi-Power lightweight Lithium Automotive Battery with RESTART Technology. Replace lead/acid battery in Hi-Performance Cars.

antigravitybatteries.com

Peter

Peter,
I'm looking to replace my dinghy battery (15 honda w/power tilt trim) and am curious what type,brand and size you used for your 20 horse ob? I'm currently using a odessy 925 battery which is small but heavy, on it's 10 year now. Were there any charging issues from the motor to battery? That is my concern with lifepo4 drawing from my engine.
Cheers J.T.

 

[mvweebles]

Peter,
I'm looking to replace my dinghy battery (15 honda w/power tilt trim) and am curious what type,brand and size you used for your 20 horse ob? I'm currently using a odessy 925 battery which is small but heavy, on it's 10 year now. Were there any charging issues from the motor to battery? That is my concern with lifepo4 drawing from my engine.
Cheers J.T.

I went with an Antigravity 480 cranking amp - 3-lbs and about the size of a thick paper back novel. $289 shipped (plus tax) AT12BS-HD-RS Lithium Motorsport Battery.

I installed it in this box and it just barely fits with terminal connections.

https://www.amazon.com/dp/B0B87X944Z?ref=ppx_pop_mob_ap_share

Please update if you pull the trigger.


@NoRain asked: My concern was having the battery run down a tad while the pulling is going on, and then the current rush when you start back up frying the alternator in the outboard.

Might be a legit concern. Anyone more knowledgeable than me have an opinion? I haven't had any issues but I confess I don't have a ton of hours on the setup. Thoughts anyone?

Peter

 

[Marco Flamingo]

I doubt a LFP battery would survive a discharge at 0F.

Not a problem, but a LFP battery would lose about 15% of its cranking capacity. That is what makes using the lead acid CCA standard (Cold Cranking Amp) for an LFP battery so misleading.

CCA, developed for rating flooded lead acid (FLA) batteries, accounts for the significant reduction in the cranking battery's "nominal capacity," usually measured at about 70F. For FLA, the CCA rating at 0F is usually 50% less than the nominal rating. We all know that we will be getting a bonus at higher temperatures. We have benefitted from it for so long that we forget about it.

Since I don't start my boat when the battery is at 0F, I rely more on the battery's nominal capacity. Say I have successfully used a 1000 CCA rated FLA battery for a few years and it needs replacement. When I started my engine at 70F, I have actually been using a battery that has 1500 amps available (its nominal rating). I have been taking advantage of the bonus. If I replace that battery with a 1000 CCA rated LFP, the new battery's nominal rating will be 1150 amps, as it only loses 15% when chilled to 0F. 1150 might spin my engine slower or not at all despite the same CCA rating. Who should I blame?

The use of CCA for LFP doesn't provide us with an accurate gauge because the temperature loss between FLA and LFP is so different. It could be that one is getting 35% less than what they thought because of the use of the CCA rating.

Not that the CCA rating is the only misleading terminology in the various LFP "start" batterys' specs. I got a kick out of reading the ad copy for the Dakota 1000 CCA battery above:
"Lithium battery equivilent to 1,000 Cold Cranking Amp (CCA) of lead acid battery engine starting power."
So, not really 1,000 CCA, just the equivilent to a lead acid battery with a 1,000 CCA rating? What the heck does that mean? The other specs don't give numbers that comes close to making that statement plausible. "Equivilant to" on what planet?

That's just one example of the weasel language. Buyer beware.

 

[Delta Riverat]

I could try this with my (3) Li Time batts in parallel which should be able to supply 1200A for 5 seconds. I do think it would start my 5.5 liter Volvos.

But I'm not going to do it because it would be a pain;
1) Disconnect the LA start batts
2) Bypass the terminal fuses on the 3 lithiums
3) Bypass the 400A class T on the house buss

I'll do it when the start batts won't -

 

[Marco Flamingo]

I could try this with my (3) Li Time batts in parallel which should be able to supply 1200A for 5 seconds. I do think it would start my 5.5 liter VolBut I'm not going to do it because it would be a pain;
1) Disconnect the LA start batts
2) Bypass the terminal fuses on the 3 lithiums
3) Bypass the 400A class T on the house buss

I'll do it when the start batts won't -

Now that you have thought about the complexity and time requirement, consider a NOCO starter for a 7 liter diesel. I got one for about $200 and consider it a bargain compared to cobbling together batteries in an emergency.

 

[man n black]

What I've noticed, particularly in the fancy Motorcoach industry that a bit ago was going through LifePo4 hype and adpotion is that many people who switched to Lithium batteries have now switched back to AGM for thier engine start batteries and kept the Lithium for the house.

Not so much for problems starting those big 15L diesels but because the alternator output of CAT and Cummins engines needed to be changed as well because the start batteries were being overcharged through the battery combiner switch or some other circuit serving both systems.

Ch

 

[GB32]

I’ve been using 8 x 3.2v Eve 180amp LiPo4 cells made up as a 24v bank to start a Cummins QSB 5.9ltr for years with no issues. The battery spec says the CCA is enough for that engine. I suspect the issue is the BMS especially if integrated batteries with internal BMS
Check out Eve Cells and this BMS

Peak 1500A Car Start up 12V 24V 460A BMS 4S 3S 7S 8S Lipo Lifepo4 Battery protection Board

No heat sink by default – Discharge 200A Add heat sink （customize)-discharge sustained up to 460A Heat sink as following :

heltec-bms.com

Beat Garry

 

[Delfin]

Thanks everyone for your thoughts and suggestions.
In reading your posts, carefully researching manufacture's information, following dozens of posts on multiple discussion boards, consulting several marine electricians and trying advertised "Cranking/Deep Cycle" LiFePo4 start batteries (and also struggling with a Victron/Epoch on the house side, a very long story for another thread, maybe) it is my conclusion that the Li industry does not have a product that will reliably start a large 6 cylinder 24 volt diesel engine. As the AGMs did, either deliver 1400cca for at least 5 seconds or get off the field of play! I am not willing to keep dropping 3k and confirming this conclusion ( yup, they may be returnable, what a pain shipping 100# anchors).

Having started my Cat 3306 24vdc system for the last eight years using LFP batteries from Lithionics, I'll have to disagree.

 

[Frankdog]

I have a 6 cylinder Cummins that used two 12v, 290Ah, 1400 CCA paralleled AGM batteries for engine starting. I tried a pair of paralleled 12v LiFePo4 advertised to be 300Ah, 1000 CCA. They wouldn't budge the motor, just clicked at me. I suspect the BMS wouldn't allow the high discharge rate the starter demanded. Regardless, is there a LiFePo4 12v (2) or a 24v battery that packs a big enough punch to spin the starter?

still to lead tech for a start battery. you do not want electronics involved in a engine starting energy supply especially on boats.