Back to the main site

Dual Battery Alternative

keithkz

keithkz

Well-Known Member
Messages
1,058
Reaction score
182
Location
Michigan Center, MI
I was looking at this at my local Interstate Battery dealer and also online this evening. I like the thought of dual batteries but don't have the time or knowledge to do it myself nor do I want to cough up the $500 plus my local Bennington dealer wants to install it. I currently have a nice Interstate battery with 800 CCA, 1000 MCA and have not had a issue yet with a dead battery after 3-4 hours of running the radio while anchored. However I would like the added security that a dual battery system provides.

This thing here is huge and does cost $200 BUT is for BOTH cranking AND deep cycle.....the best of both worlds. Part # SRM-4D:

http://www.interstatebatteries.com/cs_eStore/Products/RT/PID-SRM-4D(Commercial).aspx?dsNavigation=Ntk~SearchGroup%7C4d%7C3%7C%2CNy~True%2CNtpc~Disabled%2CAro~0%2CNs~product+Type%7C101%7C1%7C&Title=Marine+R%2FV+-+30+Months+-+1314+CCA

It has 1314 CCA, 1645 MCA, and 390 RC (reserve capacity)...that last one being the number most important for running accessories for long periods of time without the engine running and still having enough juice in it to start your motor.

Here's another link for it:

http://www.interstatebatteries.com/cs_estore/Content.aspx?dsNav=Ntk~SearchGroup|MarineDeepCycle|3|

I'm not a battery expert but this sure looks great to me as an alternative to a dual battery system. Any thoughts guys?
 
Back on my old boat I never had any issues running my battery down, granted I didn't have an amp and loads of accessories. What I had just in case though was a $60 jump-box just in case. I have used it numerous times, just not on my boat. That's my two cents, if you want peace of mind, that's probably the best bet until you start adding draw.
 
I would do a quick double check on your height availability, I still have to figure out how high I can go in the RCW. I don't know anything about batteries and wiring, but am learning as I try to compile my power needs. I will say the Blue Sea Add a Battery kit is quite simple and I'm sure you could install it yourself in its basic setup.
 
Yeah I have a REALLY nice jump start box I bought from Sears 2 years ago....their best one. I've never had the battery die on me in the boat yet so maybe I'm worrying about nothing. I don't ever have my GPS/fish finder on for any amount of time....just the stereo but that does have a 400W amp.

As far as height availability....you talking about for a new battery? I'm not restricted at all for the heght (I have an I/O and the battery sits in front of the engine and before the fuel tank). For the monster I'm looking at getting I would have to get a longer battery base though as it is way bigger than what I have.
 
keithkz said:
Yeah I have a REALLY nice jump start box I bought from Sears 2 years ago....their best one. I've never had the battery die on me in the boat yet so maybe I'm worrying about nothing. I don't ever have my GPS/fish finder on for any amount of time....just the stereo but that does have a 400W amp.

As far as height availability....you talking about for a new battery? I'm not restricted at all for the heght (I have an I/O and the battery sits in front of the engine and before the fuel tank). For the monster I'm looking at getting I would have to get a longer battery base though as it is way bigger than what I have.
Click to expand...
Yes Keith, I was talking about a new battery, sorry, I forgot you had the I/O RL. I have the RCW, so it is a concern. Speaking of which, anyone have an idea how tall the compartment for the batteries under the lounger is?
 
Looking at a jump box for mine. Any problems with this solution?

Less money. Less weight. Seems like the solution to me. But then again, what do I know. Over 60 two kids and married. Get drumber every day.
 
I have a booster pack I bring as well, mostly for filling up tubes and stuff, but I have used it twice to boost other people. Great to have.
 
Keithz, the existing battery you have is very likely also a combo cranking/deep cycle battery - most marine batteries are these days. The differences between your old battery and suggested battery are size, capacity, and obviously weight. I would consider the age and condition of the existing battery before replacing it. The proposed battery will require some modification - it is a Group 4D battery, and will require a group 4D battery tray or box. I can tell you that the battery area on my 2275RL (which is in the changing room, and has a cutout under the L shaped seating area) would 'only' accommodate a group 31 battery, as it is roughly 15 1/2" wide and 11 1/4" deep with some of that space taken up by the boot covering the through deck access hole. Even a group 31 battery with battery tray is a tight fit; as I recall, a group 31 battery box would not fit.
 
Yeah I'm not gonna replace it right now...makes no sense until at least my current battery goies bad and like I said, I have never drained it dead yet. I would for sure measure before ordering a new one but as you can see I do have room to spare:

gallery_300_298_957425.png
 
Keith,

In that space a dual battery setup would be very easy. Just add a second battery tray forward of the existing one, use a short 0 AWG cable to tie the grounding posts together, move all connections except for those to engine over to the new battery, and connect a Yandina Combiner 160 (not c100) to both battery positive terminals, and the second battery ground. You'd have a dual battery setup with isolated house and Start banks, and down the road, could add a switch to combine banks if desired. Looks like a 45 minute job tops.
 
Jim_R said:
Keith,

In that space a dual battery setup would be very easy. Just add a second battery tray forward of the existing one, use a short 0 AWG cable to tie the grounding posts together, move all connections except for those to engine over to the new battery, and connect a Yandina Combiner 160 (not c100) to both battery positive terminals, and the second battery ground. You'd have a dual battery setup with isolated house and Start banks, and down the road, could add a switch to combine banks if desired. Looks like a 45 minute job tops.
Click to expand...
45 minutes for you....all weekend for me...lol. I appreciate the tip on how to do it but you sure I can install one forward of my existing battery? It's lower.....is that still hollow there or will I have water come on after I drill the holes for the new battery tray? lol What does the switch do you are talking about? As it stand right now with what you say to do I would run everything else on the new (deep cycle battery) and keep the one I have now exclusively for starting the engine, and both batteries will charge when the engine is running correct? With the switch....what will that do for me?
 
Keith,

The area forward of your battery (read on the other side of the existing battery from the engine) looks raised and level with the existing battery in the pic - if it is not, you might want to get another opinion. You are correct the existing battery would solely be for starting your boat, everything else including your bilge pump would run off of the House battery. The switch would only be used if the starting battery somehow failed and you wanted to try and start from the House battery.
 
Last edited by a moderator:
Yeah the area forward and perpidicular to the battery (where the positive cables loop at) is lower than where the battery is now....and then from there it "V's" down.
 
You must log in or register to reply here.
Back
Top