Battery addition

S

Schuster

Member
Joined
Mar 25, 2009
Messages
213
Reaction score
2
C Dory Year
2007
C Dory Model
25 Cruiser
Vessel Name
Sea Witch
Hello fellow Cbrats,
I'm looking for suggestions for adding a battery for multiple uses. I presently have 3 Lead Acid batteries (1 year old) and really not sure if I want to replace these however I may need to. Presently when on anchor running the gps anchor watch, the anchor light, refrigerator and an ICECO freezer I tends to run the batteries down to a point that the freezer gives a low volt code.
I would like to run 1. an ICECO freezer 2. a CPAP machine overnight and 3. a trolling motor (53A max draw). I do have a honda 2000 generator but really not too excited to carry it, so may get some sort of solar.
What are my best options on a limited budget.
 
I have this: https://www.anker.com/products/a1770111 and highly recommend it. I like being able to run my ancillary devices off a separate system so I don’t have to worry about draining the essential boat batteries too far.
 
On the 2006 25 we had, we ran a 50 qt ARB fridge/freezer overnight at anchor with incandescent anchor light and did fine with (2) Group 31 lead acid batteries and did fine. We also had a 100 watt flexible solar panel on top of the bimini for recharging. No refrigerator on that boat, just the ARB and an Engel cooler with ice. We never had the gps on for an anchor alarm, though.

The onboard Norcold refrigerators of your era are power hogs. We had one on the Ranger Tug we just sold. Did not like it. As for your CPAP, plenty of people are running those on a 500 w unit like a Jackery for up to 3 nights.

It's good to have some solar. Make sure to get a MPPT charge controller, makes a big difference. A Victron or similar battery monitor is a good idea, too, if you don't have one.
 
On my 22 I can run my Norcold fridge, cabin lights (LED), fans, and other stuff overnight on one 24 size battery. After anchoring for the night (say late afternoon) I'll run the motor for 20-30 minutes before retiring for the night. If we are not departing in the morning or it will be a short run, I will run motor again for battery charging in the morning. I have two G24 batteries. One is kept in reserve for motor starting (if it is necessary). This system has worked fine for me for many years.

I would have thought that 3 batteries would be plenty of power. What size are they?
 
I added a second house battery for an underwater light for blackwater diving. I run it in parallel with the other house battery.
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My belie f with that amount of demand your best option is 200 watts of LiFePO4 batteries. I had Battle-Born on the25. You will need a monitor & battery to battery charger. Several options on mains power charging.

As a side experiment I have been running a Renogy Battery & no name Chinese mains charger, copy of Victron 702, 18 or 30 amp victron bat to bat charger.

We are on St Josh’s river, can give better details when using my computer rather than the I Phone.
 
I have one Group 27 battery for starting, and two Group 29 batteries hooked in parallel for my house. Along with the original refrigerator, I also have an Engle Freezer, Webasto diesel heater, some LED lighting, some Carfrano fans and a Cpap (without humidifier). At night on anchor I will typically run the LED anchor light from dark until I get up an hour or so after daylight, my Cpap, the refrigerator, freezer, sometimes one fan, sometimes the Webasto, and one of the LED interior lights for an hour or two after sunset. 12-15 hours later, I'm rarely less than 73% on my Vectron battery meter. I run the regular lead acid batteries. I'm not sold the other types of batteries are any better than the lead acid when you consider cost, weight and charging methods. I don't have any solar panels, but sometimes think it would be nice to have solar available. I do have my Honda 2000 generator if need be. Personally, I think your trolling motor is going to be the big draw, and you'll probably want to charge your batteries after it's use. 8) Colby
 
Thanks for the replies everyone. I probably wasn't clear that the trolling motor will be to power the dingy so would have to be on a sperate portable battery. That having been said and considering all of your comments, I think the first thing I should do is add a Vectron battery monitor to see exactly where I stand. Then replace the two group 27 house batteries with group 31"s. which would free up a battery to use for the dingy.
My next questions are how many batteries can my Honda BF150 charge without overloading it. Could I have two group 31's plus 2 or 3 group 27's? And how does the Victron monitor the batteries? As a group or individually? Lots to learn.
 
Schuster":2g1vwjhf said:
Thanks for the replies everyone. I probably wasn't clear that the trolling motor will be to power the dingy so would have to be on a sperate portable battery. That having been said and considering all of your comments, I think the first thing I should do is add a Vectron battery monitor to see exactly where I stand. Then replace the two group 27 house batteries with group 31"s. which would free up a battery to use for the dingy.
My next questions are how many batteries can my Honda BF150 charge without overloading it. Could I have two group 31's plus 2 or 3 group 27's? And how does the Victron monitor the batteries? As a group or individually? Lots to learn.
Click to expand...

Dr Bob can give you a much more technical answer, but the vectron battery meter is nice for monitoring your battery power. I have mine monitoring both my house bank and my starter battery. It can only provide most info on one battery bank, and then I have mine set to add the starter battery voltage. (That's all it can monitor on the second battery.) However on the main battery, in my case the bank of two, after I set total amphours available (as shown on the batteries), it can tell me voltage, amphours left, percentage left, and some other information on that main battery (both house batteries in my case as I have them hooked in parallel.) I have the blue tooth model, and associate app, so I can read all this info on my iphone as well, within bluetooth distance. I have noticed with two group 29's, it does take my Yamaha 150 longer to charge them that it did the one or two Group 27's. if I'm down to 75% or so, usually back up to 100% after running 3-4 hours. Perhaps I should say the simple answer is the Vectron can really only monitor a single individual battery. So with my setup, while I'm monitoring my bank of two house batteries, any condition the meter reads/shows, is a combination of both batteries in my house bank. If one battery is dead, I'm not going to know it with the other carrying the load. (ALthough, I'd probably notice something in how long it takes to run down or charge.) I have my Vectron set to also monitor the voltage of a second battery, but I believe I could also have that set to monitor the main battery temperature instead of a second battery voltage. Colby
 
Your Honda 150 puts out about 44 amps. 14 amps is generally used for the engine and its accessories, so 30 amps for other charging. The 2021 models up the charge to about 55 amps and 40 for battery charging, 30 amps at 1000 RPM.

I had no issues with 30 amps to my LiFePo4 batteries, and the Honda 150

For any battery you are going to use with the dinghy, it should be an AGM. I would get a small LiFePo4 because it is much lighter and easy to handle. Having to pass a 68 lb battery to a dingy is an accident waiting to happen. (depending on the type of dinghy). Slat floor roll up, I would be extremely careful!.

The Victron 702/712 etc, measure the current flow across the negative shunt in that particular circuit. Yes, you are wise to see what you need, before changing out batteries. There is a Chinese knock off of the 702, which I have been using for several. years and it seems to work equally as well. Cost in the $40 range, then you could buy a 50 amp 12 volt battery such as Ampere Time, LiFePO4 for $199 (weight 15#,) and would have the same energy available as a group 27 for the trolling motor. Check the video's at Will Prowse's web site on various LiFePO4 batteries.
 
Thanks Dr Bob for getting back to me. So as I understand it, I could get a knock off Vectron meter to monitor my two existing banks which consist of bank 1 is my group 27 starting battery and bank 2 is 2 group 27 house batteries.
And for the dingy (8'10" inflatable keel with plywood floor) get a small 50ish LiFePo4 battery to juice the 53A max trolling motor. I would charge that by solar panel to a controller or via Honda EU2200i to a battery charger.
I watched some of the Utube videos by Will Prowse and will spend a little more time studying different ones. From that I did learn that there are a wide range of LiFePo4 batteries out there and you don't have to pay top dollar to get good quality. Since I'm using this battery to also supply power to a CPAP machine I think I'll probably go to a 100ah battery. Thanks again.
 
Most of these shunt amp meters, measure the performance of one battery at a time. I have set them up with two shunts, where you can switch the battery with a single meter. The meter measures all functions on one battery, and then voltage only on a second battery.

Or you can just put one in the common negative from both batteries, and measure the total use.

On the last 25, I had two shunt type ammeters. One on the Li bank,(freezer, refrigerator, inverter--microwave and induction burner) the other on a FLA bank which carried the rest of the house function.

The reason at that point for the second FLA battery, was that initially no LiFe battery was rated for motor starting. (BMS being set up for that high current draw is basically the issue). Now a number of batteries are setup for outboard starting. I would make the entire boat LiFePO4 if I had to replace the conventional FLA or AGM batteries.
 
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