How are the batteries paralleled? How is the charger connected?
That fellow is Ryan Ellison one of the founders of Dakota Batteries and acting CEO.
Lithium Batteries
- Thread starter Benny17441
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Not complicated is relative. Most boat batteries are killed due to lack of care / mismanagement by their owners. Lithium is certainly more complex and requires more considerations when installing them. They are not "maintenance" free either... So if a good portion of boat owner's don't take the time to maintain their flooded/agm batteries, you need a very very robust electrical design to ensure that lack of care/attention to lithium won't have disastrous effects. And yes, Lifepo4 can have a thermal runaway.
I'll take the advice of someone who advises ABYC and multiple boat manufacturers and who's called upon by insurance companies when electrical fire occur (Nigel) versus someone who's main income is from selling lithium batteries advertised as "drop in" (Ryan is a partner in Dakota Lithium...). His boat was extensively modified to accept Lithium house batteries....
If you're not sure, call your insurance company and ask them what they require to cover you in case you modify your electrical system..... don't trust blindly everything you read/hear on the internet!
Its not complicated, but for the conflicting people whom think they are an expert.
Most batteries are killed from Over or undercharging LifePo4 is the same.
All batteries can experience thermal runaway, most Lifepo4's are designed with this risk in mind, others are not even though it can still happen
Lithium is not more complicated, its just more important you follow the charge discharge rules and fuses etc that the other technologies/chemistries.
Insurance companies are the last person you should consult and then only to ensure if you have insurance your covered. They are in business to make sure you never ever claim and how best to avoid paying you, they have their interest at heart, not yours. So yes consult to make sure your covered, however technically they are the last person to listen to.
And yep don't trust blindly what you read, including me, nor the others. Apply logic, research and what if questions.
While I have Lifepo4 on board, I personally am far more concerned about the lithium batteries in my DJI Drone and all here should be more concerned about the other Lithium technologies that they have on board. You should know that unless you have recently and specifically upgraded your fire extinguishers, they will help little with Lithium. If anyone has an example of a LifePo4 battery fire on a boat I would love to be corrected, but before you send them to me, or jump on my case, I will suggest that the cause was not LifePo4, but pour infrastructure it was connected to and the fact that LifePo4 did not give up or sag as a typical AGM or Gel might, and the fire did not start with LifePo4 in which case its not a lifePo4 problem. Do you blame the gun for killing... no you blame the user.
Most batteries are killed from Over or undercharging LifePo4 is the same.
All batteries can experience thermal runaway, most Lifepo4's are designed with this risk in mind, others are not even though it can still happen
Lithium is not more complicated, its just more important you follow the charge discharge rules and fuses etc that the other technologies/chemistries.
Insurance companies are the last person you should consult and then only to ensure if you have insurance your covered. They are in business to make sure you never ever claim and how best to avoid paying you, they have their interest at heart, not yours. So yes consult to make sure your covered, however technically they are the last person to listen to.
And yep don't trust blindly what you read, including me, nor the others. Apply logic, research and what if questions.
While I have Lifepo4 on board, I personally am far more concerned about the lithium batteries in my DJI Drone and all here should be more concerned about the other Lithium technologies that they have on board. You should know that unless you have recently and specifically upgraded your fire extinguishers, they will help little with Lithium. If anyone has an example of a LifePo4 battery fire on a boat I would love to be corrected, but before you send them to me, or jump on my case, I will suggest that the cause was not LifePo4, but pour infrastructure it was connected to and the fact that LifePo4 did not give up or sag as a typical AGM or Gel might, and the fire did not start with LifePo4 in which case its not a lifePo4 problem. Do you blame the gun for killing... no you blame the user.
Don’t you mean ”don’t worry about the rest, as long as the rest includes a multi stage charger with settings compatible with a LFP battery, an externally regulated alternator also with an LFP profile and perhaps an alternator temp sensor, and a drop in BMS rated for the maximum expected inrush current from any windlass or winch it may power”?
I die a little every time someone suggests getting advice from their insurance company about what should or shouldn't be done on their boat.
If you’re staying in the US you probably can find an insurer that doesn’t care.. ours doesn’t. But for international coverage it might matter. If you follow the FB group for Lithium batteries on boats you will see some people with issues. One insurance company requires DIY batteries to be signed off by an ABYC electrician… which they are reluctant to do.
Yes, these are a new set of 2) Humsienk 100Ah 12v smart batteries. Yes, they have Bluetooth, so I can monitor the status.
They are wired to the house load only, and are NOT charged at all by the alternator.
L ike I mentioned, HumsiENK gave me the charge parameters to “equalize” the batteries before connecting them in parallel. This was supposed to get the. Both 100 SOC and same voltage. That is not my daily charge profile. I am using a Victron charger with a Li-Ion profile.
Unfortunately, the HumsiENK app will not display the individual cell voltage. They told me they are working on it (apparently in conjunction with WattCycle), but not available yet.
i don’t think that the both of the BMs’s are shutting off at any given point. But you will see some times where one or the other battery is not contributing to the load. Usually when the load is very light. But one battery is always keeping the lights and radio on…
I have been one the hook for 2 days (going on second night tonight) and have been monitoring the battery status in a spreadsheet. I will share that if anyone cares. I don’t really have a way to charge when off shore power, except to jump the start battery to the house bank when the engine is on and the alternator is charging the starter battery. Not very efficient, and today, I motored a total of 30 minutes.
Home tomorrow and back on shore power.
Greg
I watched this a while ago, they had a a large bank, ad they were pulling negative and positive leads off the same battery IIRC.
My house bank is only 2 batteries, same manufacturer, bought at the same time. Negative lead off one battery, positive lead off the other one. Jumpers between the 2 pos and the 2 neg terminals.
Charger pos+ is connected at the battery switch and negative runs to engine ground. Negative on battery bank goes to Renogy shunt, then to engine ground.
Greg
No actually I don't. Bottom line is if you look closely at the spec's of AGM & Gell anything you have setup charging those will NOT damage !!! LifePo4. You wont necessarily get the best out of your LifePo4's, but you will still be better off. I changed NONE of those until last year when I got hit by lightning and had to replace the solar charger, so yes I bought one (Victron) with LifePo4 profile. This is my whole point I find frustrating. For sure I would not do it without a BMS and preferably one I can control. If people are still using old style chargers (ie non multi stage) then yep they should have been changed well before this. But it doesn't (and mine don't) have to have a LifePo4 profile. Yep better if it does, or better still if you can adjust it yourself. But my point if you only had a basic multistage charger, nothing in there will damage your new LifePo4's. You don't need external Alternator regulators. They don't generally change them in car drop in for example. Yep if you have some old 30-40 amp cheap junk alternator on there, that cant get past 13.8 volts then yep you have a problem, but that problem existed before you changed to LifePo4's. Temperature charge regulation for most of us is not required. If your in Canada where its below zero its probably a smart idea, or if your chargeing system can exceed that of LifePo4 charging then yes, although the BMS should protect against that, if your worried about cooking your Alternator for that to happen it means the load is higher than the alternator can deal with. LifePo4 will not suck more out of the alternator than it can supply, but it will take almost all of what its given, so if the alternator is putting out 100amps but it cant do that without overheating, that problem is in the alternator. BMS inrush Windlass, winches etc. I have an American boat which are typically power hungry. I have a 150Amp BMS this is more than sufficient for most boats under 60'. I dont have the tools to properly measure inrush but with 80amp microwave draw, and winches that can reach 100 amps, I would expect the in rush would be at least 100% higher than that, probably more like 4 times. The default settings for short circuit was up at 800 & 1000amps DC, by trial and error, with my wife hitting the toaster and Microwave and me on the anchor winch all at the same time a short circuit setting of 180Amps is more than enough and I have since scaled that back to 110, because those 3 things never all go at once. People talk about balancing the cells. Yes in an ideal world thats 100% correct, but its also true of the other technologies. If you have a larger bank of LifePo4 and perhaps have two BMS units in Parallele as suggested above getting that to balance is a nightmare, and what do people think is happening inside the dropins, that you dont see, exactly the same as what has happened for years with AGM Gel, or go back to wetsel and a Hydrometer tests. People say you cant use LifePo4 for start battery, mine works just fine, people say you cant mix AGM/Gell and LifePo4, you can and I did, its not what you want to do, but no explains why not and the implications. The maijor thing wrong with mixing these Technolgies and chemistries, is that because LifePo4 sits at a high voltage when at rest, it will dissipate power (effectively charge) your AGM/Gells at night, and depending on charge cut off's you may not get fully charged LifePo4's. However if you have and existing automated batter switch between House and start, such as BEP 722 or similar you can retain your Start battery. Lastly people talk about retaining the start battery incase of a BMS disconnect while charging resulting in blowing up diodes in the alternator. Well yes like all of what these "People" say such things can happen. But conside this. For years people swapped out car batteries with the motor running, they put there mates car battery in started there car then removed there mates put there own back. Quite probably if that car had been running at 2000 rpm maybe it would blwo diodes too, but I never herd of such. Now come to boats. I will use myself as an example. My charging systems are capable of putting out aroound 150amps from genset, around 90 amps from main engine, and around 50 from solar. Because my BMS came set and the software defaulted to some crazy loads ie 800amps and above and because I was concerned and learning about LifePo4 I actualy want the BMS to assume a short and disconnect the battery as soon as anything even a little out side the norm occurred. So in my case a load of over 120 amps for 30 seconds and a load/short 230amps is considered 100 usec it disconnects. So i created quite a few disconnects in my testing. I suspect because in my case there is almost never no load, due to a fridge radio computer, fan lights inverters etc this is possibly why I haven't blown diodes. For most of us, considering LifepO4 I would suggest the chance of absolutely no load are slim, and that fro this to be a problem it would need to occur when your charging at a a high rate. Anyway like I said when I started to respond to this 90% out there will disagree and that's just fine by me, Im just trying to open peoples eyes's that things may not be as they are often portrayed.
I'm wondering if the long run from the charger's negative terminal to the battery is contributing to the problem. Is there a negative bus bar? If so, putting the charger negative on that instead of the engine would shorten the run and reduce the resistance from the wire. Where are you measuring charging voltage, at the battery or the charger?
I monitor several catamaran-focused forums where many (if not most) of the boats have lithium banks. I haven’t heard of any insurance denials over this question. Please reference
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A friend went to install LFP batteries on his boat, his insurance company required that it be installed by an ABYC Marine Electrician. I have also heard stories, not verified, that some insurance companies would only insure if the batteries were made by a US company. Presumably so they could sue the company if things went south.
It is prudent to contact your insurance company if you are planning major changes in your boat to ensure they will continue to insure you. This may be an insurance company requirement. From the renewal letter I just received:
While it doesn't specify the electrical system, when making a change to LFP and given the controversy and misinformation floating around about Lithium batteries, better to ask them if it will affect your coverage.
More and more manufacturers are moving towards over-charge protection. Many batts already have it eg: Li-Time, Redodo, PowerQueen, Epoch, Wattcycle etc. Watt cycle is already testing a fix Epoch fixed theirs. It took Epoch a very long time to roll the fix out.
Manufacturers have moved to this because in order to survive a 5+ year warranty, with customers who insist on using lead acid chargers, with 2-4+ hour absorption cycles, they had to..
Insurance companies can deny coverage or not renew, this is why many of them require surveys every 5 years. It's not unusual for an insurance company to require certain items corrected either prior issuing coverage or within the first 30 days. Lack of safety equipment, leaking fuel tanks, insufficient hull metal thickness, excessive wood rot in the hull and electrical hazards are often reported by surveyors and the insurance co will require these rectified immediately. On the electrical side, things that get picked up are missing/incorrect fuses, wires exposed to chafe, wrong types of wires, poor wire connections (crimps).I monitor several catamaran-focused forums where many (if not most) of the boats have lithium banks. I haven’t heard of any insurance denials over this question. Please reference
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Probably not an issue with new Catamarans that come from the factory with lithium, but certainly can be an issue with DIY electricians that are not aware of marine electrical guidelines and generally accepted workmanship.
In the survey's I've seen (40+) in the past 10 years, I'd say about 1 in 5 had an item that required immediate attention as a condition of insurance. As boaters transition to lithium and get into their 5 year survey, there will likely be a lot of incorrect wiring being picked up (not my opinion, this is reported by local marine electricians/mechanics that are spending a lot of time fixing owner's mistakes).
Insurance Co frequently apply minimum standards. Sailboat owners in Florida are required to replace standing rigging on a set interval. Steel boats are often required a minimum 4mm hull thickness below the waterline. Unsecured flooded batteries are often quoted as a "must fix" item as conditions to insurance. So yes, your insurance CO has something to say if you want them to cover your toys!
In my case (working with one of the largest marine insurer in western Canada), the electrical refit / upgrade to Lithium represented a significant investment. To have the vessel insured for the additional value, they required the receipts and confirmation that all work was completed IAW ABYC E11 and E13.
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Without knowing the individual voltage of each cell, there is no way of determining what is going on or monitoring the state of health of the battery (other than disassembling it and manually measuring each cell). In a marine environment, you really don't want the BMS to EVER disconnect during normal operation (ie: during normal charging/discharging). Either your charge settings are incorrect, the battery is defective or your cells are severely out of balance (which you have no way of knowing).
You get what you pay for... .... can you return them for a more reputable brand?
40 posts and only 2 answer the OP's question.... shall we get back on topic?
Ok, but then…
So which is it?
Then there’s:
Really? It’s the alternators fault and not the installer who didn’t address any problems that might occur when switching to LFP?
Ok that’s your boat. The point is not everyone has your boat. People need to look at their specific setup when changing to LFP. We regularly sustain over 150A, btw… and use LFP to start the engines…
Also, blown diodes from voltage spikes only occur when there is significant current flowing… which isn’t the case in your car battery swap scenario.
Yes there are people who over blow the issues going to LFP. But just advising to drop them in and don’t worry about the rest is bad advice.
Will stated that that by all info he has seen, this issue is only relating to the 300Ah mini. None of the other Watts cycle batteries are affected. It is a glitch in the BMS installed in that case and will likely be resovled very quickly.
First off, it should be noted that with LFP (LiFePo4) batteriers, they are safer than flooded lead acid batteries. FLA batteries can and do explode due to the release of hydrogen gas. [Remeber the Hindenburg?] Maine Sail has offered a cash reward to anyone who can provide evidence of a fire or expolson of an LFP battery and to the best of my knowelge, he has not yet needed to shell out any cash. They can provide enough current that other components will over heat and they then cause a fire but that is true of any large battery bank.