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Battery and Charging System Upgrades

May 8, 2013
277
Hunter 40 Dataw Island, SC
Hi all,

I'd like to focus some questions for MaineSail if he's willing to pass on his fantastic knowledge and opinions but anyone, feel free to chime in also:

I'm planning a complete battery and charging system overhaul and upgrade for an 86 Hunter 40 Legend. Originally the boat had 2 8Ds, a 20 amp Charles AC charger, and the original 60(?) amp Yanmar alternator with an ASR-4 regulator. My first battery replacement cycle was to deep-six the 8Ds, replaced with 6 Group 31 12V 105 AH for 600-ish AH capacity, and upgraded to a 140A alternator. This current system is 7 years old now, batteries are done, regulator has failed, alternator still in good shape but never put out rated power due to single V-belt (learned about that from MS!) and time to retire the Charles AC charger.

So, here's the planned changes and upgrade options. Note: I am a pretty good craftsman, do most of my own work and not afraid to rip things out and rebuild/remodel for a better outcome.

Batteries (Trojan brand for all options): Option 1: 6 6V deep cycle golf cart. Will add optional watering system. 600+ AH total, dependable, mostly bullet-proof. Downside - won't fit current space due to height. Would require using carpentry skills to fit or relocate batteries. Option 2: 6V Gel. Almost as much AH, will fit current space (actually improves it). Downside - cost 2X, narrows charging options, possibly harder to replace in remote locales. Option 3: 12V Group 31 Gel. Equal AH bank to 6V Gel. My logic to 12V vs. 6V vs. 8D. If a 12V G31 battery fails, I can remove it and lose 1/6th of capacity. If a 6V fails, I lose 1/3rd. If an 8D fails, I lose 1/2. Even in the gel batteries, are the 6V still better than 12V, again assuming Trojans?

AC charger: Per MS recommendation, Sterling 60A Pro Charger with remote.

Alternator: Add either Balmar or Electromaxx serpentine belt kit to actually be able get all the amps from the alternator.

Regulator: open to suggestions before going with ASR-5 or equivalent.

I have a wind gen currently but will be adding solar soon. That's another topic entirely! Needless to say, all cables and wiring will be upgraded/replaced for the new install.

The cost of the Gel batteries doesn't scare me off, nor does AGM. Which is truly better? I like less maintenance and no need to equalize with the gels, that's why I want to go that direction. Still can't go wrong with plain old golf cart batteries though, if in the end they are the best option.

Thoughts and suggestions?

Thanks, Mark
 
Sep 15, 2009
6,241
S2 9.2a Fairhope Al
gel give you many more cycles..agm are about 1/3 to 1/2 of that and they both are great in not having to water every time you think about it along with the fact they don't gas off like flooded....wet are easier to find......6v wet give you the most amps/hrs per set and least money spent ...i use agm only because i can get them cheap and they are 12v and fit in my limited space ...if it was me and my money was a cornucopia i would go with fire fly or even the more expensive lif pro actually it would be fire fly....based on the reports from mainsail they will take a discharge down to very low (50% state of charge ) and bounce back to full without damage after recharging
 
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Maine Sail

Moderator
Feb 6, 1998
11,037
Canadian Sailcraft 36T Casco Bay, ME
Batteries (Trojan brand for all options): Option 1: 6 6V deep cycle golf cart. Will add optional watering system. 600+ AH total, dependable, mostly bullet-proof. Downside - won't fit current space due to height. Would require using carpentry skills to fit or relocate batteries. Option 2: 6V Gel. Almost as much AH, will fit current space (actually improves it). Downside - cost 2X, narrows charging options, possibly harder to replace in remote locales. Option 3: 12V Group 31 Gel. Equal AH bank to 6V Gel. My logic to 12V vs. 6V vs. 8D. If a 12V G31 battery fails, I can remove it and lose 1/6th of capacity. If a 6V fails, I lose 1/3rd. If an 8D fails, I lose 1/2. Even in the gel batteries, are the 6V still better than 12V, again assuming Trojans?
Option #1 Always a good option
Option #2 Don't be fooled into paying more than you should for the Trojan GEL. It is made for Trojan by a company well known for their excellent GEL batteries in Pennsylvania. The cycle life of the 6V GEL is rated the same as the 12V 31. Stay away from the 8D form factor..

Trojan flooded batteries are good but expensive. Trojan GEL are not really a "Trojan battery" but still excellent. The Trojan AGM's are not yet on the street as they have had some setbacks with their new factory.

Alternate Option #3 Firefly AGM batteries. These batteries are designed to be cycled to 80% DOD and they are very, very, very sulfation resistant meaning they are a very good choice for a PSOC environment.. They are available in a G31 case only and Ocean Planet Energy is who you want to contact..




AC charger: Per MS recommendation, Sterling 60A Pro Charger with remote.
Excellent charger and excellent remote and excellent warranty. I sell a TON of these chargers and have not yet had a single one come back...
Alternator: Add either Balmar or Electromaxx serpentine belt kit to actually be able get all the amps from the alternator.
There are more options in this area now. If you are dead set on Balmar vs. Emaax I would steer you towards Balmar.

Regulator: open to suggestions before going with ASR-5 or equivalent.
The Balmar MC-614 hands down.. The older ARS-4 did have some issues, which were addressed in the ARS-5. However the ARS-5 is designed to produce half the field current that the MC-614 can. With electronics lower heat and less work always means a longer life and the MC-614 will work less hard than the ARS-5 does.. Even with the ARS-4 they lasted a long time. The biggest issue is usually human error in the instillation location. NOT IN THE ENGINE ROOM! In the last 10+ years I have sold or installed well in excess of 200 of the MC-612 & MC-614 regulators and not had a single failure.



The cost of the Gel batteries doesn't scare me off, nor does AGM. Which is truly better?
For a long cycle life in a PSOC environment properly charged GEL batteries exceed the longevity of standard AGM batteries. The Firefly AGM is the game changer here as it has acceptance rates of AGM but cycling performance that actually exceeds GEL. The secret of Firefly is the patented Carbon Foam grid. While not really public knowledge these are a "hybrid" AGM meaning the electrolyte is not really a standard liquid absorbed into the mat but rather a special process which allows a GEL electrolyte to be absorbed into the glass mat construction. The batteries are new and demand is out-pacing production but Bruce Schwab at OPE can get them.
 
Jun 6, 2006
6,983
Hunter 40.5 Harrington Harbor North, MD
If you don't have the battery capacity to accept 140 amps for an extended time (50-80% SOC charging) then I'd not recommend upgrating to a serpentin belt upgrade. Clearly a 100Ah battery bank will not accept 140 amps for more than a few minutes and then only when compleatly disgharged while a 1000 Ah bank could sustain 140 amp for over an hour. The key to all this is developing a charging/storage/usage system that is balanced. Massive charging capacity with no storage is dumb, massive storage with out a large load is also dumb.......
storage, charging capacity and loads should be balanced. Start with the loads and how you use them. I have a spread sheet that does a lot of the calculations so you can see what does and does not work well.
One note: it is MUCH more efficient to use electricity (solar/wind) as you produce it. ie it is better to run the reefer at full blast all day (and turn it off at night and use the holding plate) while the solar panels are working than to try and store the energy in the batteries (and not use the holding plate). has to do with charge/discharge efficencies.
 
Sep 15, 2009
6,241
S2 9.2a Fairhope Al
I though you could limit the amps the alt put in the batteries with a balmar regulator if so then it seems to me that you would better effiency using a 140 and setting to 100 amps max thus never over heating the alt
 

Maine Sail

Moderator
Feb 6, 1998
11,037
Canadian Sailcraft 36T Casco Bay, ME
I though you could limit the amps the alt put in the batteries with a balmar regulator if so then it seems to me that you would better effiency using a 140 and setting to 100 amps max thus never over heating the alt
He is talking about a 675Ah bank so a 140A alt running at a current limit of say 115A-120A is a mere .17C charge rate......... It is always wise to derate the alt using belt manager as it will simply last longer.....
 
May 8, 2013
277
Hunter 40 Dataw Island, SC
If you don't have the battery capacity to accept 140 amps for an extended time (50-80% SOC charging) then I'd not recommend upgrating to a serpentin belt upgrade. Clearly a 100Ah battery bank will not accept 140 amps for more than a few minutes and then only when compleatly disgharged while a 1000 Ah bank could sustain 140 amp for over an hour. The key to all this is developing a charging/storage/usage system that is balanced. Massive charging capacity with no storage is dumb, massive storage with out a large load is also dumb.......
storage, charging capacity and loads should be balanced. Start with the loads and how you use them. I have a spread sheet that does a lot of the calculations so you can see what does and does not work well.
One note: it is MUCH more efficient to use electricity (solar/wind) as you produce it. ie it is better to run the reefer at full blast all day (and turn it off at night and use the holding plate) while the solar panels are working than to try and store the energy in the batteries (and not use the holding plate). has to do with charge/discharge efficencies.
So you're saying it's better to accept constant belt wear and increased heat from slippage, plus not being able to control the alternator output except by belt slippage?

I agree with the concept of a balanced charging system, sorry I didn't manage it before. I'm trying to do better this time.

I don't quite understand your efficiency/usage comment. If I attempt to utilize as much of my charging potential as actual usage when it's available, then don't I have to increase my total charge ability to compensate? And I now have to change my refrigeration? And I have to adhere to a spreadsheet? I wanted to enjoy my next cruise. Sigh...
 
May 8, 2013
277
Hunter 40 Dataw Island, SC
He is talking about a 675Ah bank so a 140A alt running at a current limit of say 115A-120A is a mere .17C charge rate......... It is always wise to derate the alt using belt manager as it will simply last longer.....
Thanks MS. Are the Firefly batteries, being AGMs, capable of accepting the higher (140A) charge rates?
 

Maine Sail

Moderator
Feb 6, 1998
11,037
Canadian Sailcraft 36T Casco Bay, ME
Thanks MS. Are the Firefly batteries, being AGMs, capable of accepting the higher (140A) charge rates?

Even with a flooded bank of 675Ah you are only at a charge rate of .17C. The Firefly accepts high current like other AGM batteries do. The time in bulk will be longer with a Firefly because you can discharge it to 20% SOC then recharge to 80-85%SOC (depends upon how large current source is).

With standard AGM's you will be cycling from 50% SOC to absorption voltage. Still, don't expect 140A out of a 140A alternator. It will only do this when cold and then it will heat up quickly to a point where it is simply not healthy for longevity. Any good installation of a small case alt will always include current limiting via the regulator. This allows the alt to work less hard and live a very long life.
 
May 8, 2013
277
Hunter 40 Dataw Island, SC
The more I look at the Firefly batteries to more I'm beginning to like them. The Ocean Planet website said you did a review of the batteries but I can't find it on your site. Can you enlighten me?

Thanks,

Mark
 

Maine Sail

Moderator
Feb 6, 1998
11,037
Canadian Sailcraft 36T Casco Bay, ME
look here
http://www.practical-sailor.com/blog/Can-Carbon-Foam-Batteries-Meet-Hype-11694-1.html

well sorta of a review ...there is also some stuff on this site in the archives....use the search bar for mainesail firefly batteries
I ran the physical and data collection for the Practical Sailor "Partial State of Charge" testing which was published in the May & August 2015 issues. It featured the Deka/East Penn AGM, Northstar TPPL AGM, Lifeline AGM, Odyssey TPPL AGM and the Firefly Carbon Foam AGM. The Northstar and second Deka test are in the August issue the initial testing data is in the May issue..

Partial State of Charge Test May 2015

Partial State of Charge Test August 2015
 
Sep 20, 2013
12
Islander 37 Seabrook, TX
I agree on the balanced system, but would also suggest the following:
1. Consider separating out your engine starting from your house batteries. A single group 31 automotive battery would suffice for engine starting - you don't need/want a deep cycle battery for this application. I never connect my starting battery to the AC charger (it just charges when the engine is running like in my car), and it always stays charged (like in my car).
2. A 600 AHish system is probably a lot more than you really need. I have cruised extensively with a 200 AH system and seldom had to run the engine (my only charging source away from a marina) just to charge the batteries.
3. Even if your batteries will accept the full 140 A charge rate, that will drop off quickly. This should be considered intermittent service for the alternator. A vee-belt drive, properly installed, should drive a 140 A alternator easily at 2000 rpm engine speed.
4. If your charger (AC or alternator) maintains a charging voltage of 14.2 volts with a mostly (say 50% SOC) discharged battery, adding a higher capacity charger will not improve the system charge performance (the charging voltage will still be regulated at 14.2 volts) - save your money.
5. The lowest cost per hour of life batteries are the old lead/acid batteries sold at the auto parts store. Advanced batteries might give twice the life, but cost 3 times as much. Plus if your battery goes bad while you are in Timbuktu, you can get a replacement the same morning, not special ordered with shipping to arrive ???
 

Maine Sail

Moderator
Feb 6, 1998
11,037
Canadian Sailcraft 36T Casco Bay, ME
1. Consider separating out your engine starting from your house batteries. A single group 31 automotive battery would suffice for engine starting - you don't need/want a deep cycle battery for this application. I never connect my starting battery to the AC charger (it just charges when the engine is running like in my car), and it always stays charged (like in my car).
You don't actually need a starting battery for this application and a good quality deep or deeper cycle battery can become your reserve or emergency bank should a failure occur on the house bank side. Deep cycle batteries can easily be used for engine starting but start batteries should not be used for cycling. It is never a bad idea to have a second battery on-board that can serve more than one purpose.


2. A 600 AHish system is probably a lot more than you really need. I have cruised extensively with a 200 AH system and seldom had to run the engine (my only charging source away from a marina) just to charge the batteries.
Without knowing the owners needs, use or desire for how many quiet days at anchor they desire it is impossible to compare your use/needs to someone else's needs or use. A larger bank will often be cycled less deeply and thus last considerably longer. I would have to say that on today's 30'-45' cruising sailboats 600Ah is about in the middle of the range for bank capacity.


3. Even if your batteries will accept the full 140 A charge rate, that will drop off quickly. This should be considered intermittent service for the alternator. A vee-belt drive, properly installed, should drive a 140 A alternator easily at 2000 rpm engine speed.
The OP is talking about a 675Ah bank and if the alternator is set up properly and derated to approx 115A then the charging would be at .17C or 17% of the banks Ah capacity. This means roughly 1.5 hours at 115A to go from 50% SOC to about 75-80% SOC. That is a lot of bulk charging before absorption voltage is attained where the alt would finally catch a break. Even if it could deliver 140A you are still in bulk for well in excess of an hour at .2C when charging into a healthy bank.

At 2000 RPM on a typical engine, the alt the OP is talking about can deliver well in excess of 110A at 2000 engine RPM so a 1/2" v-belt will not work unless the alt is derated to about 80A.


4. If your charger (AC or alternator) maintains a charging voltage of 14.2 volts with a mostly (say 50% SOC) discharged battery, adding a higher capacity charger will not improve the system charge performance (the charging voltage will still be regulated at 14.2 volts) - save your money.
Your charger or alternator would not, and should not be at 14.2V at 50% SOC.... The absorption voltage for Trojan batteries is 14.6V - 14.8V and it takes quite a long time to bring the battery voltage to the constant voltage (CV) or absorption point. Below is a Trojan SCS-225 130Ah rated battery charged at .15C or 20A. It took 1:46 minutes for the battery to even get to 14.6V. If your batteries are coming up to absorption voltage at 50% SOC they are beyond ruined.......



5. The lowest cost per hour of life batteries are the old lead/acid batteries sold at the auto parts store. Advanced batteries might give twice the life, but cost 3 times as much. Plus if your battery goes bad while you are in Timbuktu, you can get a replacement the same morning, not special ordered with shipping to arrive ???
The typical 12V flooded batteries normally sold at auto-parts stores are not a true deep cycle battery. Golf cart batteries are where you begin to get into true deep cycling capability batteries and they cost significantly less that auto-parts store batteries when you run the math on them.
 
May 8, 2013
277
Hunter 40 Dataw Island, SC
I think MS is channeling me pretty well, though he is definitely the expert and I just stumbled into a few good ideas by accident:

1. I do have a separate starting battery but I had 3 bank charging capability on the old(current) AC charger. Will use an ACR for it with the new setup.
2. My thoughts when selecting the 600AH setup back then was I didn't want to take the batteries down to 50%SOC every time because that would reduce the battery life - with the 600AH I could sail or sit on the hook for 2 days before having to recharge from 70% SOC or so. I got more life from the current bank than expected by not working it so hard. Thinking about dropping to 450AH (ish?) with a 4 bank Firefly setup though.
3. I will defer to MS's expertise on the alternator. My experience with the alt mirrors what he describes. Again, if the batteries can accept a higher current why handicap with a lower alt rating intentionally? That just means longer engine run times for charging. I did see amp drop-off but at the time I didn't realize it was belt slippage. The v-belt IS going away!
4. Didn't quite understand your point here. Again deferring to MS on the AC charger recommendation with the Sterling.
5. Never buying cheap (poor quality) batteries again! I've done a lot of research over the last few years about batteries and there is a definite difference between brands and manufacturers. I don't mind paying a little more for good quality if it is money better spent over time.

Mark
 
Jun 17, 2012
15
Bristol 35.5 Escanaba
The least expensive energy improvement is the energy you don't use. I would encourage you to consider all of your energy usage, and opportunities to reduce your energy usage, before embarking on your battery and charging upgrades. e.g., Consider a larger holding plate for your refrigeration, with a controller to turn it on to a full holding plate charge, every time there is voltage above e.g., 13.6V. On many boats refrigeration is responsible for half or more of your total energy needs. A holding plate is a much more efficient storage of energy for a refrigeration system than electric batteries. Also consider the cost of converting all your lighting to LEDs, and efficient fans. Then develop a plan to add solar energy.
Our plan was not to have the solar panel cover all the energy needs every day, rain or shine, but to probably raise the anchor every 2-4 days, which requires the engine to be running to run the electric windlass - and top up the batteries while we motor out of the anchorage. Since the refrigeration holding plate (Cool Blue double thick holding plate), Balmar alternator and smart controller upgrade, LEDs for all lighting and 88 watts of amorphous solar panels, with two Trojan T-105s we have not had to run the engine once in over 5 years to charge the batteries. IF you are sailing at night with lots of instrumentation and the autopilot on, you probably would need more batteries and solar panel capacity, but when the sun is shining, the more solar energy you use, the more the panels will provide, up to their maximum. Marilyn
 
May 8, 2013
277
Hunter 40 Dataw Island, SC
The least expensive energy improvement is the energy you don't use. I would encourage you to consider all of your energy usage, and opportunities to reduce your energy usage, before embarking on your battery and charging upgrades. e.g., Consider a larger holding plate for your refrigeration, with a controller to turn it on to a full holding plate charge, every time there is voltage above e.g., 13.6V. On many boats refrigeration is responsible for half or more of your total energy needs. A holding plate is a much more efficient storage of energy for a refrigeration system than electric batteries. Also consider the cost of converting all your lighting to LEDs, and efficient fans. Then develop a plan to add solar energy.
Our plan was not to have the solar panel cover all the energy needs every day, rain or shine, but to probably raise the anchor every 2-4 days, which requires the engine to be running to run the electric windlass - and top up the batteries while we motor out of the anchorage. Since the refrigeration holding plate (Cool Blue double thick holding plate), Balmar alternator and smart controller upgrade, LEDs for all lighting and 88 watts of amorphous solar panels, with two Trojan T-105s we have not had to run the engine once in over 5 years to charge the batteries. IF you are sailing at night with lots of instrumentation and the autopilot on, you probably would need more batteries and solar panel capacity, but when the sun is shining, the more solar energy you use, the more the panels will provide, up to their maximum. Marilyn
Mostly done! I've already converted all interior lighting to LEDs, working on the exterior lighting. Refrigeration was converted to (not sure what to call it) standard door-opening style AC/DC a few years back with the galley remodel, separate frig and freezer at the admiral's request (demand!). She hated digging through all the stuff in the box to get at what she needed which was ALWAYS at the very bottom! Truth be told, I like it too. Plus that 30 lb. yellow fin I caught can feed us for a week or better with a proper freezer. Refrigeration is probably the biggest consumer of electricity for us but I'm building the battery/charging system to suit us, not changing us to suit it.

Solar is in the works for this summer - waiting for the new bimini to be finished so I can use the space above. Also looking hard at the new flexible panels that can be bonded to the deck. I would like to see most of our regeneration via solar eventually. The wind gen works to a degree at anchor but not at all sailing downwind so I'm also looking at hydro-generators for underway.