Conversion to LiFePo batteries

[FSH 210 Sport]

This is a post in the comment section on the first video and he hits it on the head.

This is NOT a properly conducted test and it is so sad how many people this video is deceiving. The first problem was when he does his charge test and never bothers to mention how many AMPS he tried charging the battery at. This would have been the most important information he could have provided but did not. But then he gave a very important clue when he mentioned that the battery kept shutting down on him. That sounds a lot like an internal BMS (Battery Management System) shutting down for over charge current. Reading directly from the technical spec sheet of this battery, the Max Charge Current is 50 AMPS. I assumed he was trying to charge at a much higher current then the battery was ever rated for and he has now confirmed my assumption on his most recent follow up video where he tries charging the battery again but this time does disclose that his charger is set to 95 AMPS! This is a case of absolute misuse and completely ignoring (or never even consulting) the technical specs of the battery and it’s intended use. If you try to charge a battery at TWICE it’s rated current, don’t be surprised when things get hot and the BMS does exactly as it’s designed and tries to shut off the battery but cannot because you are using an AC-DC bench tester that forces a current. Any smart charger (as you should always use in any well planned system) would not continue to push a massive charge when it detects faults. This might be a great video to show the breaking point of a battery when you double it’s rated current, but it’s not a fair assessment of it’s quality.

The second major flaw in his test is that he STARTED with an already compromised battery! Any scientific experiment without a control group is completely invalid, but we won’t get into that. He states that the battery was sent to him by a subscriber as an example of a bad battery and then proceeds to conduct tests on it, knowing it’s already bad. So we have no idea how the battery was originally used or misused by this unknown subscriber. Battle Born batteries use Flag Terminals for the positive and negative connections. There are a lot of benefits to Flag terminals but they are, unfortunately, often misused by DIYers. People have a tendency to crank down on their battery connections and the extreme leverage force of a wrench would crack the housing of any Flag Terminal. This is, again, misuse. Directly from the manufacturer, a nut and bolt should be secured to the flag terminal using a socket. Unlike an adjustable wrench (which most use) a socket applies a rotational force through the center of the bolt exerting little to no leverage force on the flag terminal. We can’t confidently say this is what happened because we are given no context to this battery’s previous life, but this is a very common misuse of Flag Terminals and could have very well happened judging by the cracked internal housing seen in the video. You can even see in the beginning of the video, before he cuts the battery open, that both flag terminals are bent inward, hinting that excessive force has been applied to them. Also, the battery case itself is a crucial structural element and you can even see how the Flag Terminals are epoxied through the lid of the battery. Note around 1:15 (

) of the video when he rips the top off and almost takes the negative terminal with it as it breaks out of the epoxy that was intended to hold it into place.

I personally visited Battle Born’s production facility in Reno earlier this year, as this is my industry, and highly recommend you do the same if you’re looking for insight into the world of energy storage. They are extremely transparent about their entire process and I believe they are building the highest quality battery on the market today. I hope this CLICK BAIT video does not hurt the company as that would be a lose/lose situation for everyone. Battle Born is the most American made lithium battery on the market today and even soon to be 100% American made. They are not inexpensive because they do not cut corners. My knowledge of batteries grew 100x from visiting and talking with their engineers and even Dr. Phares himself about everything that goes into producing a quality battery like this. No one is influencing me to write this review. I am a Battle Born customer myself and have installed, literally, hundreds of their batteries for my own business and have never had a single one fail (we install them correctly with a socket and never exceed 50 AMPS per battery of charge). They are an incredible company to work with and I’m excited for their future as they continue to create jobs for the American people. Hopefully more people will stand and point out the obvious flaws in this video instead of jumping on the band wagon with everyone else slandering a company and a production process they know nothing about.

Further, this WP guy is ignoring questions regarding other BB batteries and whether or not he has tested a new battery… and also is refusing to answer questions about he was a BB fan boy a few years back. Looks more and more like a sensationalizing video to get all those hits on YouTube using a battery with a known problem without knowing how it was treated or used to put money in his pocket, as well as the other YouTubers piling on to make their own hit count go up… transparent.

 

[FSH 210 Sport]

So, I saw yet another video on bb battery “problems”…. Had to respond. I don’t usually but I just can’t stand such poor science and what has become an obvious hit piece.

I posted the majority of what is below on WP’s follow up video, bb a new issue, but here I edited it a bit, and added a few more things at the bottom.

In regards to the continuous 100A discharge and 50A charge. WP’s vid shows that a 100A discharge to bms low voltage cut off then immediately charging the battery back to 100% via 50A max charge and was successful. It is the immediate100A discharge directly after the 50A charge that causes BMS in the battery to shut off short of full discharge due to high internal heat which is 135*F. I think this type of “continuous” load / charge testing will yield the same results in other batteries as there is no where to reject the heat built up in the battery which a natural aspect of such use of a battery. WP then goes on to say the bb battery doesn’t keep its promised “continuous” duty cycle and compares a 5000 watt inverter that has a “continuous” rating, well the inverter has fans to cool it, try putting that inverter in a box, fans and all and apply 5000 watts of load, it will shut off on high heat because there is no where to reject the heat. Pull the BB battery out of its case and run the “continuous” test and there won’t be a problem. This is simple thermodynamics.

Further, who uses a battery like this in the first place?

This type of testing is not intended to look for a fault, which in this case was supposed to be over heating of the positive terminal, it is a destruction type of torture test, to see if the same type of damage can be recreated on the bb battery but this time with a new battery, but I don’t want to get ahead of myself.

It’s a bit of a silly test, and all the other batteries on the market make the same claims of continuous 100A discharge rates and sometimes even higher charge rates and will either shutdown on high internal heat or will catch on fire.

When I watched WP’s first vid I checked my 4 BB batteries, all were pristine. Three of them make up a 36 volt trolling motor battery that has a max discharge of 52 amps, though mostly they discharge at 4-15 amps, I’d be out of trolling motor fast if I discharged them at higher rates. They charge at 25A’s. The fourth battery is a “house” battery and doesn’t see very high discharge rates, maybe 10A’s continuous throughout the day, and charges at 10A’s. These batteries have at least 30,000 miles on them being in the boat while trailered and thousands of hours on board my boat in some pretty rough conditions, again all were pristine, all posts were rock solid and the potting around the positive posts is the same red it was when delivered.

Other than once listed below, WP has not responded to any of my legitimate questions, nor has he responded to other peoples legitimate questions about how he conducted this “testing”.

WP’s first vid was testing a used and obviously damaged bb battery given to him by a “fan”, with no history of how it was used, you can even see the positive terminal is at an angle before he starts his “testing”. So torture testing a known bad battery and claiming there is a problem is bad science to say the least. In a follow up video, WP gets a new battery (with his very own money) and does back to back testing on this battery, 100A discharge to low voltage cut off then an immediately charges the battery at its max 50A charge to try and duplicate the high heat issue affecting the positive terminal, towards the end of the first 100A discharge test he uses an infra red camera and calls out temperatures of 109* and 114* on the battery terminals but doesn’t say which temperature belongs to which terminal, and is also hiding the camera screen where as in other vids he shows you the screen, seems like that should be an important distinction since the problem is allegedly the positive terminal.

He is then surprised the bms shuts the battery off on high internal heat when making an immediate subsequent 100A discharge run right after charging at the 50A max charge, the proclaims there is a new problem that it doesn’t meet the continuous duty claims..

Wait.. what?…

I thought you were going to show us how the bb battery was dangerous because it got so hot that it was melting the internal and external plastics, but as it turns out the bms safeties shut the battery off on high internal heat, AND WP made good external connections with wire of the proper size to handle the 100A current so the temperatures were low on the terminals, again, he took temperatures but didn’t tell the audience which terminal was which and 109* and 114* are not high temps.

He doesn’t mention once that there is no heat issue.

All WP did was make the case for BB about poor external connections and or underrated wire causing high external heat that is damaging the battery, in this case the positive terminal potting and the inside connection, but! That didn’t happen due to the built in safeties, further reinforcing bb’s case.

WP says he is getting a “cycling” machine built to basically torture test the bb and other batteries, full max discharge and full max charge, Again, who uses a battery this way? Max discharge then immediate max charge rate? Answer? NO ONE USES A BATTERY THIS WAY.

These are ridiculous tests, they are just a torture tests designed to destroy a battery, and or find designed in safety guards and is intentionally done to cause damage, but so far, WP’s newly purchased bb battery has not had any damage from this torture testing, no excessive temperatures, no discolored potting and no loose positive terminal, again making the case for bb that it was underrated external connections causing high heat.

Here’s a link to a good test video where a bb and other batteries are removed from their cases and run at max discharge rates with an infra red camera on the intervals. When it comes to the bb battery, the area of concern doesn’t show any high heat.

Again, it will be interesting to see WPs future vids, if he makes them, using the exact same testing protocols on other brands of batteries and see what the results are.

Additional info…
I’ve seen other people making vids about the bb batteries, one guy gets bb batteries from the dump, the freaking dump, cuts it open and the internals have rust on them, which means the case was compromised-stupid..
Another video shows clips of bb batteries being removed that were from his testing of different batteries, that particular guy says most people would not have any issues because they don’t use their batteries that way… What? Who uses their batteries like that? NO ONE DOES.

Also, WP has now had to back track on his fan boy status of bb batteries as he went to the bb factory in 2019 and deemed bb batteries an excellent battery. Ooops. Funny how he doesn’t mention any of his previous fan boy status of bb batteries when he is saying over and over again how dangerous they are until, but he started getting called out on it on his fan boy status by a growing number of people..

I’ve read through thousands of posts in these videos, talk about a dumpster fire of irrational Cro-Magnon comments from people who don’t even own bb batteries, others who do have bb batteries that have either not checked their batteries or who have, with no signs of any damage saying they’re going to get rid of them and replace them (sure you are Bucky) with new batteries.. others have said they would not send the batteries back for warranty because the owner has to pay initial shipping charges back to bb for them to investigate with the reasoning that bb is not going to warranty them, well, how would you know that? You spent a grand on each battery and you don’t want to send it back for the $150 shipping charges to get the battery either fixed or replaced? You know why? Because these people know that bb is not going to warranty them because they messed them up.

Then the same people who post comments from one video post the same comment in different video’s with the same verbiage..innuendo and posts with promised follow up vids and information that have not appeared, at least at the time of when I was looking for said info within the time frame they said the content would be up.

At one point I commented that there has been no fires associated with bb batteries, WP replied yes there had been one video, and some of his fans had seen it, but the video had been taken down, so I asked him, why do you suppose that video was taken down Will? Crickets.. But will has plenty of time to “love” all of his adoration comments in his vids..

I have investigated this issue with the same vigor that I did my initial investigation on LFP batteries, I’ve looked all over and what I have found is it is as bb states, damage has been caused by the end user. Has bb had other issues? Yep, and bb has warrantied the batteries. There are some posts of people who have installed hundreds of these batteries and have had no problems with them.

Again, bb has been in business 11 years and delivered over 400,000 batteries and not one fire or injury. BB has also partnered with several major RV manufacturers, boat builders, trucking companies for their zero emission parked power stations, stand by rail communication systems and on and on…

Could there be a problem? Maybe, but I think it highly dubious at this point, based on reading of thousands of comments in various videos and some basic rational thought and application of scientific procedures on the subject.

 

[zipper]

Good video above^^^. Once you look up BB. You get all kinds of video's put before you.

Not trying to whip a dead horse here, I am truly trying to do research for a new battery bank for the PDQ. I do like BB and would not buy the replacement battery he did.

Supposedly not an issue with the 270ah gamechanger, that I am looking at.

https://diysolarforum.com/threads/born-to-burn-the-battle-born-lfp-battery.118681/#post-1682452

 

[FSH 210 Sport]

I’ll say right up front there could be a problem.

BUT I spent decades in the electrical industry and I look at things this from a fault analysis perspective. Having said that there is a striking lack of necessary information about this guys set up, his usage etc.

1. Conductor size. What was the gauge of wire that was used to tie the batteries together and the terminal wire size? How were the batteries wired?
2. What were the affected batteries location in the bank?
3. What was the load on the bank? Was there Air Conditioning loads connected to the battery bank? What was the locked rotor amperage at start up?
4. What was the total charge rate on the bank? All LFP batteries require 10Amps of charge rate per battery, that would require a minimum of a 60 A charge rate for the 6 batteries in //.
5. How was the charger connected to the bank? Ideally this would be 6 separate chargers one for each battery, but three 25 amp chargers in // would work.
6. What was the brand of charger and charging profile used?
7. What was the DOD on the bank on a daily basis? Were the batteries allowed to discharge to 0 volts and low voltage cut off? And were they charged back up within a week?

This guy claims the red potting material was discolored around the positive terminal but in the pictures it looked like the proper color to me, and I didn’t see whether or not he said the discoloration was associated the bad batteries, and the other thing that is associated with the discolored terminals is loose terminals and there was no mention of whether or not the terminals were associated with the bad batteries. That’s some horrible fault analysis.

Warranty
I keep seeing this big surprise about the warranty process. It’s all spelled out in their warranty policy. Does no one read the 10 year warranty policy on an $800 battery before they buy it ? These batteries are designated hazardous material, so they have to be packed accordingly, and the shipping cost is commensurate with hazardous material shipping. And you can’t just take the battery in a box into a UPS store it has to be taken to a certified shipper, and that’s not talked about either.

So this guy talks about the shipping cost and the cost of repair IF the batteries are found to not be warrantable. If the battery repair is under warranty bb refunds the shipping cost and makes the repairs at no cost.

If there is a non warrantable repair required the cost is $150 per battery.

This is the case with all of these lfp batteries.

This guy says that the $500 cost of shipping and repair was not worth it to him, yet he spent $700 and change on new batteries and he will have less storage than if he had bb make the repairs. Again that’s IF the batteries were deemed to not be warrantable.

Thats some interesting math, makes seriously doubt the veracity of his claim.

I’ve seen this numerous times in posts where people say it’s too much money to do a warranty but it’s the same with other LFP battery manufacturers. I have heard that the cheaper batteries will send you one, 1, replacement battery and that’s it.

So bb has him do a series of tests before the RA is issued, this also how the other companies do returns as well. I helped a member here diagnose a problem on one of his Dakota lithium batteries, but in that instance DL was just giving him the runaround so I had him take measurements with a multimeter and had him take pics of them and email them to DL. After that DL agreed to issue the RA. The difference between DL and BB is that you get to talk to a person at bb in real time, with DL you’re lucky if you get an email response in 24 hours. The only people you get to talk to at DL are salespeople no tech support.

So again what I see in this guys video are lies of omission to make his case look good and not comply with the known warranty procedure. He tries to make a case that bb is not standing behind their warranty but bb IS standing by their warranty, it’s in writing on their website, there should be no surprise here.

It is unfortunate that his guy had four of the six batteries become non functional, that in and of itself points to something fishy in my book, thats a 66% failure rate, no way a company could survive with a 66% failure rate of its products. And what is even more fishy is him knowingly spending $700 dollars (claimed but cheapest I could find was $800) on two 580Ah batteries, when there was a very good chance he would have had to spend $0 dollars and got his original batteries warrantied and be back up to his 600Ah capacity, even if he was to have to pay for the shipping and repairs it was $500 and is still $200 (or is it really $300 see below) less than buying new batteries. Unless he knew that how he had his system configured would make the batteries unwarrantable.

His claim is that it was basically not worth it because it was a unilateral decisions on bb’s part about whether or not his batteries were warrantable, is that somehow specific to bb or is it that way to all products with a warranty? To me that is pretty lousy logic, especially since bb gave him the procedures to test the batteries before a RA was even issued, which means, bb was then sure there was something wrong with the batteries and would even be worth everyone’s time and energy to do a warranty return. I think this guy saw wp’s video, he had an issue with his batteries(probably due to his own actions, and I’d love to know his handle on that diy solar site, but I’m betting he is the guy I read about who said he had six bb batteries in his camper and was going to “check them out”) and was looking for a way to get new batteries and make some money off of his you tube hits.. think I’m crazy? There are just too many things conveniently left out. Like these new batteries have a 3 year warranty instead of 10, so had he had this problem with these batteries from 2021 he would have been out of the warranty period and SOL.

My guess is that this guy allowed the batteries to go into low voltage cut off and didn’t recharge them within a week.

Here’s the link on amazon, $809 for a two pack.

https://www.amazon.com/ECO-WORTHY-12V-280Ah-2Pack-Phosphate/dp/B0CKT2J3M9/ref=asc_df_B0CKT2J3M9?tag=bingshoppinga-20&linkCode=df0&hvadid=80470695962958&hvnetw=o&hvqmt=e&hvbmt=be&hvdev=c&hvlocint=&hvlocphy=106661&hvtargid=pla-4584070166901370&th=1

Look at the description of the product and it mentions these batteries require hazmat shipping, and they’re there to help out with a 24 hour return contact… contact how? Email ? Phone call? It’s not specified. The list goes on and on and on..

 

[FSH 210 Sport]

So I went and checked Dakota Lithiums warranty and return pages. The link below will take you to that site. DL advises you that sending a battery back has to meet DOT and FAA regs, I cannot tell if they will help you with packaging or not but it does say that you have to pay for the shipping, same as BB, but BB will send you the packing kit and forms to mail the batteries back and locate a shipper and coordinate a pick up for you. DL just gives a shipping address.

As I said above, those batteries that guy bought will leave you with the same return policies.

https://dakotalithium.b-cdn.net/wp-content/uploads/2023/09/11-Year-Warranty-Policy-for-Dakota-Lithium-Batteries-9.2023.pdf

So here is what the guy in the latest video calls a unilateral decision, he makes it sound as if BB is the only one to have that decision making process, another LIE OF OMISSION, as to whether or not the batteries will be warrantable or not.. as you can see the list is LARGE and I’m 100% that all of these manufacturers have the same list of exclusions. So for him to say that bb is not living up to its warranty is total bullshit. All that guy is doing is trying to get more hits to his U tube channel to make more money. His logic is unsound and he is just full of crap.

Again, when you deal with bb you will talk to a person, with DL and others you will exchange emails with a 24-48 hour response time.

 

[FSH 210 Sport]

One of my four bb batteries internal heating stopped working so it is heading back for a warranty repair. The battery still functioned normally, it just would not let me charge it when it was 23*. I warmed it up with an electric battery blanket and it charged up fine and still worked normally as far as discharging went.

The shipping cost was $331, which I paid upfront, bb sent me all of the shipping stuff with explicit instructions on how to apply the stickers, how to tie it down with the included straps, bill of laiden sheets, contact information of the local shipping outfit. The shipping outfit contacted me before the shipping materiel even got to me door, I arranged to go and drop it off at their location as it was easier for me and them.

Those stickers and shipping labels are on all sides of the mini pallet as well as on top of the battery box itself. That is how these have to be shipped by an individual.

If the battery is deemed to be a warranty issue then the $331 will be refunded to me, the battery either repaired or a new one sent to me with no further charges.

If the battery is deemed to not be a warranty issue then it will cost me $150 to have it repaired, which will suck but I will let everyone know either way. Then it will be shipped back to me with no further charges.




The only way to avoid this when returning for a warranty repair, for any brand of LFP battery is to buy the batteries at a store wherein you can return them to the store and they handle it. Places like Bass Pro shops sell ReLion batteries branded for Bass Pro shops, AMPED batteries are sold at scheels. Just make sure they will handle the warranty process when you buy them.

 

[zipper]

Just saw this…

 

[FSH 210 Sport]

Just saw this…
View attachment 243279

Very well said.

 

[WiskyDan]

It's about time BB addressed this to the public but they should have released something sooner.

The following info is my opinion. As we all know, opinions are like @ssholes - we all have one and this is mine.

I think the video that shows the loose lug in reply #130 and the the follow-up video by the dopes in reply #136 and #143 are hit pieces.

The battery that's shown in the video in reply #130 was sent to him by some random channel follower with no context on how the battery was used or abused. The guy had previously visited BB, got a tour of their facility, and gave a favorable review. In the comments below the video someone asked if he had reached out to BB and he said no, he was too busy. I would think that you'd want to give the company whom you had previously visited a chance to respond before publishing a video attacking their product - especially when you have no idea what the random channel follower that sent you battery did to it?

The video in reply #136 is regurgitated info with the only purpose being to sell some other manufacturers battery - it's blatant and a complete waste of time.

The video in reply #143 is just plain stupid. "I bought six BB batteries at $800 a pop and had problems with four of them. Paying to ship them back (they're considered hazardous materials, doofus!!) to be examined was deemed excessive so I just threw them away and bought these other cheap Chinese batteries". If those were my batteries, and I didn't abuse them, I'd feel very confident that if I sent it back the shipping and any repair costs would be covered under warranty. IF I abused the batteries (usage/setup) I wouldn't return the batteries because I know I'd be out of the shipping costs so I'd take that money and spend it on some cheap Chinese battery to replace them with.

In full disclosure, I have a BB 100Ah battery that was purchased 2024 and have used it for two seasons - no problems so far. I called BB twice - once before I purchased and once with a complaint and the calls were answered right away by professional English speaking people that provided all the info that I asked for. The complaint was minor - the battery does not come with a handle which is optional - pretty silly for an $800 battery and they offered to send one at no charge.

I think it's a shame that the reputation of an American company with a quality product is being dragged through the mud by people just trying to increase their YouTube views to make money.

 

[Bklenk]

Hello Everyone! New to the forum after finding this thread when doing research about switching to Lithium on my boat, and I have a few questions. I just got a new to me 2016 Yamaha 242xe that is completely stock. It currently has two sealed lead-acid batteries that I know are getting to the end of their life. I've made the switch to lithium on my travel trailer and have been very happy with them, which led me to want to do the upgrade on the boat when the time comes to replace the lead acid ones. Where I store my boat, I do not have access to power to keep the boat plugged in on a battery tender, and I like the fact that lithium will self-discharge less and last me longer. Plus, I can plug it in for a few hours before a trip to top everything off quicker. As I just got the boat, I don't know exactly what my power usage is going to be, but I would like to be able to play the radio for a while without having to worry about it killing my battery. Ok, that is the background and the setup, now on to my question.

Question number one is, do I need to do the DVSR to fuel pump hot modification if I do lithium for both my house and start batteries, since they should be at the same voltages?

Question two is, could I get away with doing a small 20ah lithium start battery and then a 100-ish amp hour for the house? Several companies are advertising a 20ah starting battery with specs that are within the range for starting our motors. From the Litime site for example, at only $190 right now
Hot Cranking Amps (HCA)：
900A
Marine Cranking Amps (MCA)：
810A
Cold Cranking Amps (CCA)：
800A(-10℃); 650A(-18℃)

Or would I be better off getting a 165ah dual purpose battery and have one battery only? These I believe have a power reserve mode to use as an emergency start.

Thanks for all the information everyone in this thread have put out and thanks for any future advise.

 

[lazergeek]

Hello Everyone! New to the forum after finding this thread when doing research about switching to Lithium on my boat, and I have a few questions. I just got a new to me 2016 Yamaha 242xe that is completely stock. It currently has two sealed lead-acid batteries that I know are getting to the end of their life. I've made the switch to lithium on my travel trailer and have been very happy with them, which led me to want to do the upgrade on the boat when the time comes to replace the lead acid ones. Where I store my boat, I do not have access to power to keep the boat plugged in on a battery tender, and I like the fact that lithium will self-discharge less and last me longer. Plus, I can plug it in for a few hours before a trip to top everything off quicker. As I just got the boat, I don't know exactly what my power usage is going to be, but I would like to be able to play the radio for a while without having to worry about it killing my battery. Ok, that is the background and the setup, now on to my question.

Question number one is, do I need to do the DVSR to fuel pump hot modification if I do lithium for both my house and start batteries, since they should be at the same voltages?

Question two is, could I get away with doing a small 20ah lithium start battery and then a 100-ish amp hour for the house? Several companies are advertising a 20ah starting battery with specs that are within the range for starting our motors. From the Litime site for example, at only $190 right now
Hot Cranking Amps (HCA)：
900A
Marine Cranking Amps (MCA)：
810A
Cold Cranking Amps (CCA)：
800A(-10℃); 650A(-18℃)

Or would I be better off getting a 165ah dual purpose battery and have one battery only? These I believe have a power reserve mode to use as an emergency start.

Thanks for all the information everyone in this thread have put out and thanks for any future advise.

I have a WEIZE 12V 60AH 800CCA Dual Purpose LiFePO4 Battery as my start battery and it works well for me. I do have the DVSR mod connected to my ignition switch.

I personally dont know if not having the mod in place will make an impact but the resting voltage is high enough to keep the DVSR engaged all the time essentially acting as a single bank all the time.

 

[Bklenk]

I have a WEIZE 12V 60AH 800CCA Dual Purpose LiFePO4 Battery as my start battery and it works well for me. I do have the DVSR mod connected to my ignition switch.

I personally dont know if not having the mod in place will make an impact but the resting voltage is high enough to keep the DVSR engaged all the time essentially acting as a single bank all the time.

Do you have a lithium battery as your house battery as well?

 

[lazergeek]

Do you have a lithium battery as your house battery as well?

Yes I have a 100Ah LifePO5 house battery, I just added the dual purpose Start 4 months ago.

 

[FSH 210 Sport]

Hello Everyone! New to the forum after finding this thread when doing research about switching to Lithium on my boat, and I have a few questions. I just got a new to me 2016 Yamaha 242xe that is completely stock. It currently has two sealed lead-acid batteries that I know are getting to the end of their life. I've made the switch to lithium on my travel trailer and have been very happy with them, which led me to want to do the upgrade on the boat when the time comes to replace the lead acid ones. Where I store my boat, I do not have access to power to keep the boat plugged in on a battery tender, and I like the fact that lithium will self-discharge less and last me longer. Plus, I can plug it in for a few hours before a trip to top everything off quicker. As I just got the boat, I don't know exactly what my power usage is going to be, but I would like to be able to play the radio for a while without having to worry about it killing my battery. Ok, that is the background and the setup, now on to my question.

Question number one is, do I need to do the DVSR to fuel pump hot modification if I do lithium for both my house and start batteries, since they should be at the same voltages?

Question two is, could I get away with doing a small 20ah lithium start battery and then a 100-ish amp hour for the house? Several companies are advertising a 20ah starting battery with specs that are within the range for starting our motors. From the Litime site for example, at only $190 right now
Hot Cranking Amps (HCA)：
900A
Marine Cranking Amps (MCA)：
810A
Cold Cranking Amps (CCA)：
800A(-10℃); 650A(-18℃)

Or would I be better off getting a 165ah dual purpose battery and have one battery only? These I believe have a power reserve mode to use as an emergency start.

Thanks for all the information everyone in this thread have put out and thanks for any future advise.

The answers to all of your questions are in this lengthy thread, please take the time to read it thoroughly. There’s a lot of great input here from different people and all the investigations that went into this.

But I’ll give you a few answers and my opinions, which are also located in this thread.

I would not recommend lithium start battery. I have a group 24 AGM battery that I use as my start battery. While there has been very good gains in the dual purpose lithium batteries I still don’t feel comfortable using one for a start battery. You need to have a lead acid battery connected to the engines while they’re running, the BMS in a LFP battery can turn the battery off under certain conditions to protect itself for several reasons, one being an over charge, if that happens while the engines are running there’s a very real possibility you will destroy the voltage rectifiers / regulators on your engines. If there’s no where for the charge current and voltage to go the diodes fry in the regulator/rectifiers. I don’t know how the start rated LFP batteries deal with this, but I do know there is only one battery that Mercury Marine will allow as a start battery and that is ReLion.

As explained throughout this thread you have to do the DVSR modification, you can either switch it manually like I do, or you can hook it up to a fuel pump hot. The resting voltage is of LFP batteries is above the DVSR drop out voltage of 12.8 V DC. You do not want the DVSR to be closed when the engine is off.

You do not want to put some tiny start battery in your boat. Some people say that’s all the wave runners or personal watercraft have is a small 20 amp hour battery and that’s mainly because they don’t have room for a larger one. You want to have a minimum of a group 24 lead acid or AGM Start battery.

You want to have two batteries, a dedicated start battery that the DVSR will isolate when the engines are not running, or manually switched so that you always have a battery that’s dedicated to starting the engines. Then you have a dedicated house battery for all of your accessory loads.

You’ll also want to have a smart shunt of some kind so can monitor the SOC state of charge on your house battery. I have a separate Victron energy smart shunt that connects to my phone.

Battery chargers. As you eluded to above, LFP batteries charge quickly, five times faster than a lead acid battery, that’s mainly due to their charge profile having a very short absorption mode. Having said that you will want to have a battery charger that can take advantage of that. In my opinion for your application especially you’ll want a Victron IP 67 battery charger that puts out 25A, it can also be set to 10A, if say you had a 100 Ah LFP battery and you were to discharge it 75%, the Victron charger will charge that battery back up in 3.5 hours, three hours at bulk and 30 minutes in absorption. The start battery charger can be 10A. Also the minimum charge rate for a LFP battery is 10A. These chargers should be mounted on board in a compartment that either has enough air circulation to allow the heat from the chargers to escape or has a hatch that can be left open enough to allow the heat to escape. Chargers should also be ignition proof meaning they can’t ignite any combustible vapors and have an IP 65 rating.

Get an AC port from NOCO to make plugging your battery chargers in easy.

Here’s a basic set up, a group 24 AGM start or dual purpose battery to start the engines that has a dedicated 10A battery charger. A 100Ah LFP house battery with a dedicated 25 A charger. The DVSR set up with a run hot so that when the engines are running the dvsr is active but when the engines are off the DVSR is not active keeping the start and house batteries isolated, this configuration also isolates the batteries when charging from shore power.

Post in thread 'DVSR modification'

Oct 5, 2025

BEP DIGITAL VOLTAGE SENSITIVE RELAY User Manual

View and Download BEP DIGITAL VOLTAGE SENSITIVE RELAY instruction manual online.

manualmachine.com

• FSH 210 Sport

• 

Thread 'DVSR help...'

Jun 19, 2019

I wouldn’t ask if I hadn’t searched all over. I can not find the tutorial with pictures for modifying the DVSR when adding a 2 bank charger. I just noticed that the red light on the DVSR was on during and after charging while the switches were off. Could someone post the link or pics or instructions for the mod? Summer is almost here!

• MicahH
• Replies: 173
• Forum: Electronics-Stereo/GPS/Chartplotter/Electrical etc

 

[FSH 210 Sport]

I’ve also received the initial shipping information from FedEx.

 

[WiskyDan]

"It looks like we are approved" seems like a silly way to reply to a customer about a warranty claim?

 

[FSH 210 Sport]

"It looks like we are approved" seems like a silly way to reply to a customer about a warranty claim?

It is an interesting turn of phrase…but I can see the intent.

 

[FSH 210 Sport]

The replacement Battle Born battery was delivered to my house this morning. I opened it to give it a cursory inspection and it looks like a brand new battery.



The shipping fee of $331 was also refunded to my Credit Card account as of this morning.

So once the battery got into the inspection and repair departments it took a week to make the warranty decision, ship the replacement battery back to me and credit my cc account for the shipping charges I paid up front. All of this was how the warranty spelled out how things would go, Dragonfly / Battle Born stood behind their product warranty.

When I outfit my toy hauler with LFP batteries I will be seeking out BB for that purchase.

 

[FSH 210 Sport]

BTN….. cleaned up the wiring a bit.


I made up some new jumpers as the originals that the dealer installed were looking a little anemic.