Batteries
- Thread starter Hcard
- Start date
The battery box is under the aft berth (in case you didn’t already know that), and will hold a pair of group 24s easily. If you want to go larger, I was able to just jam in a pair of group 27s several years ago, back to 24s now. Type of battery will depend on your intended use of the boat. I day sail and weekend, occasionally a week cruise so I find dual purpose starting/deep cycle are fine for my needs. Enjoy , great boat!
Clayton
‘89 32-200
Clayton
‘89 32-200
Do you have a battery charger onboard? If so, what brand/model? What are your electrical needs (engine starting, navigation lights, VHF radio, cabin lights, electric tea kettle etc)? How's your budget? Does the boat have battery boxes? Battery cable connections? One-Two-Both-Off switch? 110/30amp shore power connection? Solar Panels?
Inquiring minds will want to know...
Reader's Digest version:
Group ratings are physical sizes of the battery. Amp Hours are how much use vs. time you can expect, estimate your use at 1/2 of the AH rating or for all types of lead batteries or you'll cause sulfation which lead based batteries do not like. Batteries "cycle" and "age". The less you discharge them and bring them back to full charge after use the longer the batteries will last (assuming your charger is set correctly for the battery type.) CCA and MCA ratings are how much juice a battery can kick out when operating a starter.
Lead battery types: Flooded Lead Acid are the most affordable and require quarterly maintenance. AGM can be installed in any position without fear of dumping sulfuric acid all over the place, with minimal maintenance but more cost. Gel are good for lower amp discharges and tolerate higher temperatures, but at a higher price. These batteries do not like a partial state of charge and should be trickle charged between use and brought back to full charge after use.
Carbon Foam behave more like Lithium Iron and use lead chemistry. They have half the Lithium Iron price, don't mind a partial state of discharge, and can be depleted more than 50% without undo damage. Expect four or five dollar signs, but about three times the lifespan of other lead based batteries.
Lithium Iron Phosphate are the bee's knees of the marine battery world and are very pricy up front, require an accurate BMS (Battery Management System) and are not good very starter batteries for the most part. LiFePO4 is very stable compared to laptop, phone, cordless drill, Tesla, Leaf, and Prius batteries. The alternator on your motor will also require some protection should the BMS cut off while the alternator is putting out a charging current. I mention them here because they are a possibility, although require a longer conversation.
The answers to the questions above will help narrow suggestions to all of these alternatives.
Congratulations on your purchase and welcome to the exclusive inclusive community of Ericson Yacht ownership.
Max
Inquiring minds will want to know...
Reader's Digest version:
Group ratings are physical sizes of the battery. Amp Hours are how much use vs. time you can expect, estimate your use at 1/2 of the AH rating or for all types of lead batteries or you'll cause sulfation which lead based batteries do not like. Batteries "cycle" and "age". The less you discharge them and bring them back to full charge after use the longer the batteries will last (assuming your charger is set correctly for the battery type.) CCA and MCA ratings are how much juice a battery can kick out when operating a starter.
Lead battery types: Flooded Lead Acid are the most affordable and require quarterly maintenance. AGM can be installed in any position without fear of dumping sulfuric acid all over the place, with minimal maintenance but more cost. Gel are good for lower amp discharges and tolerate higher temperatures, but at a higher price. These batteries do not like a partial state of charge and should be trickle charged between use and brought back to full charge after use.
Carbon Foam behave more like Lithium Iron and use lead chemistry. They have half the Lithium Iron price, don't mind a partial state of discharge, and can be depleted more than 50% without undo damage. Expect four or five dollar signs, but about three times the lifespan of other lead based batteries.
Lithium Iron Phosphate are the bee's knees of the marine battery world and are very pricy up front, require an accurate BMS (Battery Management System) and are not good very starter batteries for the most part. LiFePO4 is very stable compared to laptop, phone, cordless drill, Tesla, Leaf, and Prius batteries. The alternator on your motor will also require some protection should the BMS cut off while the alternator is putting out a charging current. I mention them here because they are a possibility, although require a longer conversation.
The answers to the questions above will help narrow suggestions to all of these alternatives.
Congratulations on your purchase and welcome to the exclusive inclusive community of Ericson Yacht ownership.
Max
Hcard
Member III
Thank you Clayton, great information. I will use the boat pretty much as you do, so your guidance here is of great help. Many thanks and will do As you suggest. Thank you for taking the time to reply to my post.
Hcard
Member III
hi Max, thank you for your reply. This is great info, frankly I will have to find Out most of it. I dont have charger or solar, but is something I would like to put in the future. The electrics in the boat arte pretty simple. Yes there is a box with cables, lights, electronics (the ususal). The information you provided me with as well as Clayton will help me a lot. Thank you for replying and for your welcome words. I am looking forward to enjoying the community, contributing when I can. All the best to you.
Good, you don't have a marine battery charger yet. That will be necessary to install with the batteries.
Start a "which battery charger" thread when you get around to that, or better yet jump onto a historical thread after a Google search. For what it's worth, I run every major purchase through the gang here, which is happy to act as a sounding board, and has many Ericson-specific experts.
An expert is a guy who just did it last week. He knows more than anybody this week.
Start a "which battery charger" thread when you get around to that, or better yet jump onto a historical thread after a Google search. For what it's worth, I run every major purchase through the gang here, which is happy to act as a sounding board, and has many Ericson-specific experts.
An expert is a guy who just did it last week. He knows more than anybody this week.
Slick470
Member III
Depending on your usage, you may or may not need a charger. Between a long motor in and out of our marina and a small solar panel to top things off, while we are away from the boat, we've gotten away without a charger, or even shore power for years. Think about how you use your boat, what on your boat actually uses battery power and for how long, then put together a conservative energy budget and go from there. Changing lights out to LED and upgrading electronics can make a big difference in the calculations, especially if you use your boat at night. Be careful with LED's though and make sure the ones you buy have been tested to make sure they don't put out any interference.
There are a lot power budget spreadsheets online that you can find if you search. I used to have a pretty good one, but I'm drawing a blank on where to find it. Perhaps others have good suggestions there.
There are a lot power budget spreadsheets online that you can find if you search. I used to have a pretty good one, but I'm drawing a blank on where to find it. Perhaps others have good suggestions there.
Link to another charger thread:
ericsonyachts.org
Battery Charger Advice
Looks like I am in the market for a new battery charger and am hoping that somebody out there can give me some good advice. It appears that bank three of the old Ray Jefferson Model 155 Regulated D.C. Battery Guard has taken a crap. Imagine that after 35 years! Anyway, I'm a little confused...
Hcard
Member III
Noted, Many thanks.
Hcard
Member III
Thank you for your input, Hugo
Here's a nifty little tool for estimating energy use from eMarine Systems. The amps suggested are pretty accurate/average from what I've seen. The tendency is to over estimate on the first go, but a reasonable edit will correct where necessary.
When I lived on the hook I was able to get by with a solar trickle charger, oil lamps for heat and light, a camp style stove, carried my own water (and snuck into marinas at night to borrow their spigot) and got by quite comfortably rocked in the cradle of the deep. But since then I've gotten a bigger boat (or two), have become very fond of refrigeration, have a bigger motor to start than the ol' Honda 8hp outboard (with built in generator) and a bigger battery bank to go with them. Still using solar though, for a bit more than just a trickle charge...
Max
When I lived on the hook I was able to get by with a solar trickle charger, oil lamps for heat and light, a camp style stove, carried my own water (and snuck into marinas at night to borrow their spigot) and got by quite comfortably rocked in the cradle of the deep. But since then I've gotten a bigger boat (or two), have become very fond of refrigeration, have a bigger motor to start than the ol' Honda 8hp outboard (with built in generator) and a bigger battery bank to go with them. Still using solar though, for a bit more than just a trickle charge...
Max
Congratulations! What hull number and what is your boat named?
there are more battery threads and info and opinions and it can actually make you go glassy-eyed after a while. My two cents, after learning by doing it all wrong at first... best idea to get started is KISS.
12 Volt (versus 2X6 volt) lead acid batteries are the best bang for your buck. Trojans among others are good quality. Lead acid are familiar and the charging is straightforward. Other battery chemistries require special charging and can be ruined quickly by incorrect charging.
A good battery charger should be one of your first purchases and don't go 'cheap' on this. Another thing that kills batteries very quickly is PSOC (partial state of charge). It is very important to bring a battery back up to full charge asap after use and not leave it partially charged. A 'smart' battery charger will do this; full charging typically requires a fair period on 'float' to fully top up a battery and motoring alone and charging off the alternator may not do this (there are three stages of charging; bulk, absorption, and float).
All batteries in a single bank should be identical and purchased at the same time for effective charging. The term 'bank' can be confusing at first; a 'bank' can be one battery only, or two or three connected in parallel and drawn from simultaneously.
Given minimal requirements as you have, two single battery banks might be adequate. Small diesels and Atomic Four engines can easily be started with a real 'deep cycle' battery so there is no need for a dedicated starting battery which is expensive, takes up valuable space, and is rarely used. You can have two banks... one currently in use and one in 'reserve' and use them alternately to exercise them and keep aware of their capacities. The starting/deep cycle batteries are a compromise and are not true deep cycle which is what you really need for cruising.
12 Volt (versus 2X6 volt) lead acid batteries are the best bang for your buck. Trojans among others are good quality. Lead acid are familiar and the charging is straightforward. Other battery chemistries require special charging and can be ruined quickly by incorrect charging.
A good battery charger should be one of your first purchases and don't go 'cheap' on this. Another thing that kills batteries very quickly is PSOC (partial state of charge). It is very important to bring a battery back up to full charge asap after use and not leave it partially charged. A 'smart' battery charger will do this; full charging typically requires a fair period on 'float' to fully top up a battery and motoring alone and charging off the alternator may not do this (there are three stages of charging; bulk, absorption, and float).
All batteries in a single bank should be identical and purchased at the same time for effective charging. The term 'bank' can be confusing at first; a 'bank' can be one battery only, or two or three connected in parallel and drawn from simultaneously.
Given minimal requirements as you have, two single battery banks might be adequate. Small diesels and Atomic Four engines can easily be started with a real 'deep cycle' battery so there is no need for a dedicated starting battery which is expensive, takes up valuable space, and is rarely used. You can have two banks... one currently in use and one in 'reserve' and use them alternately to exercise them and keep aware of their capacities. The starting/deep cycle batteries are a compromise and are not true deep cycle which is what you really need for cruising.
Tom Metzger
Sustaining Partner
I think Slick laid it out for you. Basically, if you don't have refrigeration or some other large load you don't need a shore power charger. You can buy a lot of diesel before you approach the cost of a decent marine charger. Besides, you can't use the charger when you are out cruising. Only use one battery per trip, pay attention to your voltmeter and try to keep it above 12 volts. If it falls below start your engine. Keep the engine above 1500 rpm for efficient charging. Our small diesels don't use enough current to require a starting type battery. Instead use a straight deep cycle. They are better at what you want them for.
Important: Never leave the battery switch in the "BOTH" position unless you are actively charging.
Heresy alert: Cheap batteries work fine and will last a long time if maintained (Walmart, etc.). Clean tap water won't hurt them and is much, much better than leaving the plates exposed while you hunt for a source of distilled water. DO NOT waste the still on your boat making water.
On a previous boat I went 18 years without a charger with four of us on board. OK, full disclosure: that was before the invention of the power usage spreadsheet.
Being conservative, I powered a couple of miles after leaving the dock or anchorage before putting up the sails.
Important: Never leave the battery switch in the "BOTH" position unless you are actively charging.
Heresy alert: Cheap batteries work fine and will last a long time if maintained (Walmart, etc.). Clean tap water won't hurt them and is much, much better than leaving the plates exposed while you hunt for a source of distilled water. DO NOT waste the still on your boat making water.
On a previous boat I went 18 years without a charger with four of us on board. OK, full disclosure: that was before the invention of the power usage spreadsheet.
Being conservative, I powered a couple of miles after leaving the dock or anchorage before putting up the sails.Tom is right about budget batteries... if well-maintained, they can do the job for several years. And battery maintenance is a learning curve so you may as well blow out cheap ones first : ) I had a Sears Die-Hard battery that came with my first boat. It was old then and I used it for several years after, even being badly treated. And that was before LED's.
And as stated, never ever let the electrolyte get down too low... if you see the tops of the plates, your battery will be damaged irreparably. Distilled water best, but any water better than none.
And yes, a voltmeter is a necessary tool on a boat. 12 volt batteries are not really 12 volt batteries... at full charge they should read around 12.65 volts. Never let your battery get below 12.5 volts which is approx 50% discharged. If it gets to 12 volts, it is fully depleted and may be toast. Too-deep discharging is as bad as PSOC and low electrolyte for ruining batteries.
Recently charged batteries may read aroind 12.8+Volts btw... this is due to a 'surface charge' so leave the battery for 24 hrs to get a true reading OR run the blower motor for a minute or so to remove the surface charge before taking a reading.
The guy on the dock across from me would run his diesel to charge his batteries, until I had a bit of a talk with him regarding the rest of us not being able to breathe. Beware of whom is downwind : )
And as stated, never ever let the electrolyte get down too low... if you see the tops of the plates, your battery will be damaged irreparably. Distilled water best, but any water better than none.
And yes, a voltmeter is a necessary tool on a boat. 12 volt batteries are not really 12 volt batteries... at full charge they should read around 12.65 volts. Never let your battery get below 12.5 volts which is approx 50% discharged. If it gets to 12 volts, it is fully depleted and may be toast. Too-deep discharging is as bad as PSOC and low electrolyte for ruining batteries.
Recently charged batteries may read aroind 12.8+Volts btw... this is due to a 'surface charge' so leave the battery for 24 hrs to get a true reading OR run the blower motor for a minute or so to remove the surface charge before taking a reading.
The guy on the dock across from me would run his diesel to charge his batteries, until I had a bit of a talk with him regarding the rest of us not being able to breathe. Beware of whom is downwind : )
Tom Metzger
Sustaining Partner
A fully depleted 12 volt lead-acid battery is defined as being at 10.5 volts. This is not "dead". Discharging to this level will reduce the battery's life, but a deep cycle battery can sustain many such cycles. That said, fully discharging the battery is bad practice and should be avoided because it does reduce the life. Best practice is to stay above 50% SOC (state of charge) when possible.
The 50% SOC is a complex value. It depends on many things, such as temperature, discharge or charge rate, time since last charge, etc. For the average boater trying to stay above 12 volts when not under heavy load (>8 amps for a Grp 24 battery, or C/10) is an easy way to do it. The best way is to use a battery monitor, however, it really isn't necessary for the average weekender without a fridge.
I truly appreciate the knowledge shared here. My last set of batteries were Kirkland from Costco "dual purpose" and lasted 6+ years. They were Interstates badged for Costco. Reviews of the newest version weren't so great so I went with batteries from Advance Auto Parts. Less than $200 for a pair of 24s. Drawing a blank on the brand, sorry. My next set I will remember this thread and just go for deep cycles thanks to Tom's info re low draw from the diesel.
There is nothing wrong with any of the multitude of battery types available for marine use. Everyone will have their preference for the managing electrical loads. The trick is to match the battery type with the conditions and intentions of use.
Flooded lead-acid batteries have been around since 1859, so they have that going for them. Oxygen and hydrogen are byproducts when charging which is what happens to the sulphuric acid when it evaporates, thus the recommendation to add water. This is part of the reason these batteries are meant (required by ABYC) to be kept in a covered container (battery box) vented to the atmosphere.
H and O can explode if sparked, rapid gas producing charge rates are discouraged. A good rule of thumb for L/A batteries is to limit charging amperage to 25-30% of the AH rating to limit off-gassing. The other reason to box the battery is to contain the Sulphuric Acid in case of a spill. A good charger or solar controller will be programmable to operate within the limits of the battery type selected.
(Other lead batteries like AGM and Gel are "starved" of acid and are valve regulated which is why you can install them in just about any position, even sideways, although they won't cycle as many times as a properly maintained Flooded Lead Acid.)
Adding water maintains the magic chemistry that makes electricity. What you're really doing is diluting the specific gravity of the Sulphuric Acid from about 1.84 to 1.265 for a "fully charged" battery. Remember those squeeze bulb hydrometers in your grandfather's garage? It'll go far toward an honest assessment of battery condition. If all your cells (six on a 12v battery) are the same specific gravity the battery is in good health.
An inexpensive and more accurate refractometer is an improvement over the hydrometer and available from Jeff Bezos. Distilled water is a really good idea when maintaining specific gravity and readily available at your local supermarket (at least around here).
Over discharging and/or a partial state of charge of Flooded Lead-Acid batteries causes the lead sulphide plates to build up a plaque (crystalline) of sulfates. This inhibits the production of the ions that make the magic happen. If a cell or cells become more sulfated than the other cells you'll get a different specific gravities and an unhealthy battery on its way out. This is a bit like good dental hygiene, avoid plaque, or add water to adjust specific gravity.
Some chargers will periodically and intentionally overcharge the Flooded Lead-Acid battery to recondition the lead plates from sulfation. This "stage" of charging is called Equalization and should not be applied to other battery types. Returning the batteries to full charge after use should make this stage largely unnecessary.
Voltage as a measured rate of charge is a snapshot in time and not a super accurate measure of overall charge level. You'd have to "rest" the battery for 24 hours to get a more accurate state of charge reading. Battery monitors are more accurate as they measure over time, but sometimes a snapshot is all you really need. There is also a "threshold level" beyond which appliances (like lightbulbs) become less than useful, usually about the time you need them most, or 11.9 V, whichever is greater. (Remember the dimming light of those late hours reading by flashlight under the covers? Threshold level...)
Don't overcharge, don't over-discharge, avoid partial state of charge, return to full charge after use, trickle charge when in storage, maintain your specific gravity and you'll get years, and years, and years, and years of reliable use from Flooded Lead-Acid. Can't be bothered? Choose another battery type or knock off a few of those years.
Oh, by the way, that thing about not storing batteries on concrete is a myth. Might have been true in 1859 when the boxes were made from wood but we've come a long way since then.
Flooded lead-acid batteries have been around since 1859, so they have that going for them. Oxygen and hydrogen are byproducts when charging which is what happens to the sulphuric acid when it evaporates, thus the recommendation to add water. This is part of the reason these batteries are meant (required by ABYC) to be kept in a covered container (battery box) vented to the atmosphere.
H and O can explode if sparked, rapid gas producing charge rates are discouraged. A good rule of thumb for L/A batteries is to limit charging amperage to 25-30% of the AH rating to limit off-gassing. The other reason to box the battery is to contain the Sulphuric Acid in case of a spill. A good charger or solar controller will be programmable to operate within the limits of the battery type selected.
(Other lead batteries like AGM and Gel are "starved" of acid and are valve regulated which is why you can install them in just about any position, even sideways, although they won't cycle as many times as a properly maintained Flooded Lead Acid.)
Adding water maintains the magic chemistry that makes electricity. What you're really doing is diluting the specific gravity of the Sulphuric Acid from about 1.84 to 1.265 for a "fully charged" battery. Remember those squeeze bulb hydrometers in your grandfather's garage? It'll go far toward an honest assessment of battery condition. If all your cells (six on a 12v battery) are the same specific gravity the battery is in good health.
An inexpensive and more accurate refractometer is an improvement over the hydrometer and available from Jeff Bezos. Distilled water is a really good idea when maintaining specific gravity and readily available at your local supermarket (at least around here).
Over discharging and/or a partial state of charge of Flooded Lead-Acid batteries causes the lead sulphide plates to build up a plaque (crystalline) of sulfates. This inhibits the production of the ions that make the magic happen. If a cell or cells become more sulfated than the other cells you'll get a different specific gravities and an unhealthy battery on its way out. This is a bit like good dental hygiene, avoid plaque, or add water to adjust specific gravity.
Some chargers will periodically and intentionally overcharge the Flooded Lead-Acid battery to recondition the lead plates from sulfation. This "stage" of charging is called Equalization and should not be applied to other battery types. Returning the batteries to full charge after use should make this stage largely unnecessary.
Voltage as a measured rate of charge is a snapshot in time and not a super accurate measure of overall charge level. You'd have to "rest" the battery for 24 hours to get a more accurate state of charge reading. Battery monitors are more accurate as they measure over time, but sometimes a snapshot is all you really need. There is also a "threshold level" beyond which appliances (like lightbulbs) become less than useful, usually about the time you need them most, or 11.9 V, whichever is greater. (Remember the dimming light of those late hours reading by flashlight under the covers? Threshold level...)
Don't overcharge, don't over-discharge, avoid partial state of charge, return to full charge after use, trickle charge when in storage, maintain your specific gravity and you'll get years, and years, and years, and years of reliable use from Flooded Lead-Acid. Can't be bothered? Choose another battery type or knock off a few of those years.
Oh, by the way, that thing about not storing batteries on concrete is a myth. Might have been true in 1859 when the boxes were made from wood but we've come a long way since then.
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Was just going to post about this. After separating the two 85AH lead acid batteries in my bank for awhile, one was at 12.3 V. The other was 9.6V. Was toying with the idea of just replacing the bad battery. I have no idea how old the good one is, but the bad one has a 2013 sticker on it.
Is it conventional wisdom to replace both batteries in the bank together?