Batteries Went Dead Overnight - Beginner

[hellosailor]

odyssey-
Battery guys ran somewhere between high class call girls and used car salesmen on the scale of "trust me". But having said that, I'd tell you to drag your batteries into a local distributor and have them load tested. If someone who comes out to your boat has the right equipment, they can load test them on the spot, but they're often not doing things quite the same.
If running your batteries dry gave them a chance to sulphite and get ruined, then they are ruined. Load testing will tell that.
If the capacity is just not adequate, again, you need to use a meter and run numbers and see what's up. Like poker, or croquet, the rules are not really difficult IF you read up on them before playing the game.
So I'd strongly suggest looking at old threads and getting some basic "12 volt marine" books to learn how to manage this stuff--or else you will forever be at the mercy of those battery guys.

senormechanico-
My mother has a car just like yours. Once or twice a year, dead battery. Jump start, charge, load test...and it is all perfect. Alternator, perfect. Dome lights, disabled. Connections, clean and tight. Parasitic loads, never. Funny thing though, others with the same model have reported the same recurring problem, and there's a suspicion that because most of the new cars are using "power management controllers", sometimes the car's internal computers are getting confused, leaving something fully powered up and killing the battery. Possibly leaving the remote door locks fully active (instead of "sleeping" them) possibly doing something else that is clever and invisible.
AAA is glad to sell her a new battery, but funny thing, the last one they said was bad, is now over two years older and still holds a "full" charge, except perhaps once a year, when Area51 goes active. Hmmmm.....

[skipmac]

Originally Posted by jwcolby54

I don't think that is true, although what you mean by "recover" is relevant here. What is true is that:

1) Most batteries will take ten or so complete discharges.
2) Each complete discharge DOES damage the battery, resulting in the battery able to hold less current the next time (will not "fully charge", will hold less and less charge each time.)
3) The length of time it remains fully discharged matters a lot. Fully discharging a battery just one time, but leaving it that way for a year will likely kill it. Leaving it that way for a couple of days will most definitely not. It WILL definitely damage it to some extent.

Total discharge certainly isn't good for the battery but definitely doesn't kill them completely, even if left to sit discharged.

Had a brand new battery in the car when my wife left it at the airport with the headlights on for two weeks. Got back and it was as discharged as a battery could be. Got a jump, drove home and used that battery for a few years. Estimate it lost about 25% of it's theoretical life span and some of the Ah capacity but worked fine to crank the engine during that time.

[skipmac]

Originally Posted by jwcolby54

Good for you! I'm happy that you are happy!.

Since you bring it up no, I'm not happy at all with my little coolers. Feel like I wasted about $150 for coolers that at best will keep something "not hot".

I've even brought them in the house the night before a trip and run them for 12-14 hours in a cooler environment trying to cool them down before the trip to the lake but really didn't help at all. I guess if you're using them when the ambient temps are 65-70 F then they would keep stuff actually cold inside.

Now I'm not saying that a $1000 (or more) marine refrigeration system is a cost effective replacement. If it was I would have put one on my ski boat. Just saying that a cooler at 60-70 F doesn't really work for me as a "cooler". For my requirements they're just an expensive picnic basket but they do keep the sandwiches out of the sun.

[theodyssey]

can't thank everyone enough for the input. after running [biking] around town for a few days, I finally found out that my alternator had gone bad. that being said, your all's suggestions gave me a crash course in all of this, and - as we speak - The 12 Volt Bible is being bought.

thank you all.

[a64pilot]

It may not be a good solution for a ski boat, but Sailor Chic's budget solution is a dorm fridge run off of an inverter.
Much more energy efficient than a Peltier cooler, but without the cost associated with an ice box conversion or an Engel.

Lowes has one for $89 plus tax of course
http://www.lowes.com/pd_617647-33112...l+refrigerator


Sent from my iPad Pro using Cruisers Sailing Forum

[mcarling]

Originally Posted by ramblinrod

I completely disagree with your position that standard lead acid batteries have no place in the boating community.

That has never been my position, so you're simply making a false attribution. I have never suggested that people should replace lead-acid batteries that are working fine. I have never taken the position that standard lead acid batteries have no place in the boating community. I have suggested that we're past the time when it makes sense to install new lead-acid batteries, but that is very different from the position you falsely accused me of taking.

[reed1v]

If your sailing to foreign shores, and perhaps around the world, old fashion lead acid batteries are the way to go. Single 2 cells strapped together to make whatever voltage you want. Will last for many years if kept topped up. Simple to maintain. Huge power reserve(unless you are running ten microwaves at the same time). Plus lead batteries are everywhere around the world so easy to replace/repair(Yup, the turks can repair your old batteries). They also handle abuse quite well, except if you draw them down to dead. Simple enough to add an electronic monitor that will stop any power drain that might bring them that low. Keep them in a faraday cage with GFI interface to all leads, and they are fairly immune from lightening strikes(we found that out twice).

[ramblinrod]

Originally Posted by mcarling

That has never been my position, so you're simply making a false attribution. I have never suggested that people should replace lead-acid batteries that are working fine. I have never taken the position that standard lead acid batteries have no place in the boating community. I have suggested that we're past the time when it makes sense to install new lead-acid batteries, but that is very different from the position you falsely accused me of taking.

Semantics.

It still makes lots of sense for lots of people to install standard lead acid batteries instead of LiFePo4.

Ramblin Rod
Marine Service Provider
About Sheen Marine

[mcarling]

Originally Posted by ramblinrod

It still makes lots of sense for lots of people to install standard lead acid batteries instead of LiFePo4.

About that we have a difference of opinion.

[skipmac]

Originally Posted by mcarling

About that we have a difference of opinion.

My take so far on LiFePO is they take a good bit of knowledge and understanding of how they work to install and use them to their capacity without killing them. Do you disagree with that?

[mcarling]

Originally Posted by skipmac

My take so far on LiFePO is they take a good bit of knowledge and understanding of how they work to install and use them to their capacity without killing them. Do you disagree with that?

Without a metric for "a good bit of knowledge and understanding", I can neither agree nor disagree. I would put it this way: The amount of knowledge and understanding needed to install and use LiFePO4 batteries is similar to the amount of knowledge and understanding needed to install and use lead-acid batteries, with two differences that currently more or less balance each other. 1) Most of the charging devices on the market are configured by default to charge lead-acid batteries. 2) However, one who doesn't understand how to use and charge lead-acid batteries is going to destroy them anyway. If (or when) charging devices are sensibly configured to charge LiFePO4 batteries, then their use requires much less knowledge and understanding than lead-acid batteries, because charging and discharging over the 1%-99% range is not very harmful to LiFePO4 batteries.

[skipmac]

Originally Posted by mcarling

Without a metric for "a good bit of knowledge and understanding", I can neither agree nor disagree. I would put it this way: The amount of knowledge and understanding needed to install and use LiFePO4 batteries is similar to the amount of knowledge and understanding needed to install and use lead-acid batteries, with two differences that currently more or less balance each other. 1) Most of the charging devices on the market are configured by default to charge lead-acid batteries. 2) However, one who doesn't understand how to use and charge lead-acid batteries is going to destroy them anyway. If (or when) charging devices are sensibly configured to charge LiFePO4 batteries, then their use requires much less knowledge and understanding than lead-acid batteries, because charging and discharging over the 1%-99% range is not very harmful to LiFePO4 batteries.

Well let me elaborate a bit on my take. First I'll mention that I have a degree in electrical engineering so the terminology and technology is not totally incomprehensible to me. And, since I've pretty busy with work and finishing up my refit I haven't been very motivated to get into the LiFePO in the detail I think is required to go LiFePO. but I did read through the very long discussion on CF and a couple of articles and this is a short summary of what I think I learned.

Installation. LiFePO comes in individual cells so you have to wire them together to make a bank. No horrendously complicated but still something for a battery newbie to deal with. Also you have to prep the batteries by balancing the cells; top balance, bottom balance or you can destroy the batteries. Not an issue at all with FLA batteries.

Charging. Net necessarily a lot more complicated that FLA but very different and requires more attention to the process or you can destroy the batteries. I read that LiFePO prefer to be fully charged then stop. Discharged fully before recharging. So you have to watch the SOC and only charge at the right time and only to the right state. FLA you can recharge or top off the batteries whenever it's convenient. Got a nice, sunny day? Max out your solar. Tied up at the dock every day or so, top off the batteries and maybe run an EQ cycle.

Plus I see some recommending fairly complex battery monitoring systems, some saying you don't need them.

Bottom line, there's at least a couple of gothcas with LiFePO that can destroy the batteries and if that happens you could be out a few thousand dollars. Screw up FLA system and you're out a few hundred. Yes you can kill FLA batteries but you generally have to work pretty hard at it and in most screw ups you loose some life and capacity but they aren't immediately dead. With LiFePO I believe they can be completely dead immediately.

The last point, unless one has a few grand to invest up front buying into LiFePO is not cost effective. Sure over the long run it appears that there's a good payout but every cruiser doesn't have that many boat bucks in a lump to switch.

[hellosailor]

skip-
Even on charging, there is considerable disagreement. Depending on the battery type (NiMH, lead, lithium) and even within the same type, I've heard some major companies say "40 to 75%" or "90 to 95%" and they've spent years, literally, cycling packs through different loads and charge rates between different voltage points, trying to optimize the overall battery life.
Oddly enough, it seems that no one (corporate) has wanted to invest hundreds of thousands into testing lithium batteries under the general load cycling conditions that the tiny marine market might have. Which is very different from urban transit busses, industrial fork lifts, and the occasional 787.
And with so many people tinkering with battery chemistry and the odds of that, and pricing, changing well before "payoff" time on any newfangled system...I don't think lead acid of any kind is pointless, let along "inferior", in any general way yet. Maybe soon, but not yet, for sure.

[Cheechako]

I always see these battery type-amp hours-amps/hour-monitor? or no monitor? debates and just have to chuckle.
It's a little like the fuel gauge in your car. You set out with full tank in the morning and know that 500 miles later you need to replenish. To me that's an analogy for simple voltmeter.
Now you could put fuel use sensors in the fuel line the way they do on jet aircraft. But in the end, yep... you still know you are going to need to get gas at days end. You didn't need to know how many micro ounces you were using along the way. The gauge is close enough and knowing a bunch of details along the way doesn't change anything.

[skipmac]

Originally Posted by Cheechako

I always see these battery type-amp hours-amps/hour-monitor? or no monitor? debates and just have to chuckle.
It's a little like the fuel gauge in your car. You set out with full tank in the morning and know that 500 miles later you need to replenish. To me that's an analogy for simple voltmeter.
Now you could put fuel use sensors in the fuel line the way they do on jet aircraft. But in the end, yep... you still know you are going to need to get gas at days end. You didn't need to know how many micro ounces you were using along the way. The gauge is close enough and knowing a bunch of details along the way doesn't change anything.

In general I am in total agreement. Over the course of a day or week what's happening on the milliamp level or +/- 0.01V basis just isn't that necessary.

Just one difference between the fuel gauge and battery monitors that can end up shortening the life of your house batteries. With a fuel gauge fuel in is fuel in, period. Use 10 gallons, pump 10 gallons back in and all is good.

With a battery, use 10 amp hours, put 10 amp hours back in and you aren't back to even. Now I'm certain you're well aware of this but there's plenty of boaters for whom electricity is a black art, all totally mysterious. Plus as you know, the battery monitor (except from what I hear the new Smartgauge) doesn't necessarily give you an accurate reading on the SOC of the battery or available amphours. which further limits the usefulness.

All that being said, I do like my monitor. Lets me get an instantaneous shot of amp usage for any system, amp hour usage over time, voltage, etc. All that needs intelligent interpretation but overall it's good information.