Marine batteries

[Bloggsy]

Time to replace the 2 boat batteries. I have a voltage sensitive relay fitted so the starting battery is always charged first and then the accessories battery gets charged therefore you don't have to worry about having a position 1-2 1&2 changeover switch. And I run all my accessories off the second battery. My questions are what would be the most suitable batteries to purchase. I have been told that a deep cycle battery for the accessories would be best but I was of the belief that deep cycle batteries don't like being fast charged as the outboard alternator would do. Also it would be easier to be able to charge both batteries with the one charger as I have a ctek port dash mounted. I currently have 2x Century Marine Pro 680 fitted which came with the boat but in previous boats I have always used Supercharge Sea Master batteries MFM50 I am restricted for room so cannot go any longer that 170mm max.  

[Rebel]

The two brands you mentioned are both good.

Your call.

Cheers.

[Bloggsy]

Oops length should be 270 mm my mistake.

[Sharknado]

Optima blue top, they are a dual purpose AGM so can be used as a cranking battery & as a powerbank.

 

They are more on the expensive side so If you cant afford 2 then maybe get a cheaper crank.

 

AGM's are normally on the large size in comparison to cranking but the Optima's are good for having a lack of room. 

 

https://www.optimabatteries.com/en-us/bluetop-dual-purpose-deep-cycle-and-starting

 

AGM's will still work with a VSR but have you ever tested how many volts is getting to the AUX, if the voltage isnt that of what a cars alternator would produce then you may need a DC-DC charger?

But if the current system is working fine the the VSR will do the job.

[Bloggsy]

Interesting quote from Suzuki page on batteries "Caution: Avoid using deep cycle battery, maintenance-free battery, lithium battery or gel cell battery"

[dmck]

On 10/6/2020 at 10:07 AM, Bloggsy said:

Interesting quote from Suzuki page on batteries "Caution: Avoid using deep cycle battery, maintenance-free battery, lithium battery or gel cell battery"

very interesting!!

Can you post the link to this pleasr?

I goggled for it but couldnt find it.

[Bloggsy]

https://www.suzukimarine.com.au/parts-and-servicing/top-5-outboard-maintenance-reminders/battery-specs/

 

I put into Google Suzuki outboard battery specifications

[Fishop]

I have the same setup as you I just went with 2 century marine batteries with a VSR.  I cant see a time when my accessories will require anything like a deep cycle.  I usually only fish a spot for an hour or two and my sounder, stereo, lights, radios etc I doubt will flatten a battery in that time.  I have installed volt meter's for each battery to keep an eye on it just in case.

[antonywardle]

The suzuki link looks like it is recommending a normal starter battery for the outboard. I went with a 4WD N70 in mine. Its a lot cheaper, is good with the bumps and the CCA is quite high (640 from memory) Swap your other one out for a Deepcycle. Google Giant Power 140AH 12V Deep Cycle AGM and that will probably be good for you.

You can use them for starting, is just not recommended. Thats where the 1-2-both-off switcch is handy. Plus you can turn off all the power when you are at home. I have this and a VSR. and it works for me. Take a portable jump starter with you too. You;ll probably use it more for helping other people out that yourself. That said, I did leave the lights on my car on the weekend and thought I'd need it to get my car started so I could my boat out!.

How have you got your toys connected to the second battery? Is it a lead on the 1-2-both-off,  if you have ones, witch? If it is, then you are most likely running them from what ever battery you've got selected.

 

 

[61 crusher]

On 10/14/2020 at 9:33 AM, antonywardle said:

went with a 4WD N70 in mine. Its a lot cheaper, is good with the bumps and the CCA is quite high (640 from memory) 

What did that cost you out of curiosity 

[Renegade460]

Just a side note VSR's do not prioritise charge to any battery, they both charge at the same time.

[antonywardle]

9 hours ago, 61 crusher said:

What did that cost you out of curiosity 

I think it was around $100. They are at $114 now, Maxus 640CCA, and at that price, you can replace them every two years if you get worried about them. I had them in my prado too.

[Bloggsy]

My set up is that I have one battery solely for the motor and one battery for everything else sounders - auto pilot- fridge - electric reels - pie warmer etc. Of course the motor is left running when using electric reels and I have a volt meter read out and a low voltage alarm on the sounder for when motor is not running.

VSR Operation: The Voltage Sensitive Relay (VSR) allows two batteries to be charged at the same time. When the engine is started and the start battery reaches 13.7 volts, the VSR engages, allowing two battery banks (start and house) to be charged simultaneously. When the voltage drops below 12.8 volts (eg. the engine is stopped), the VSR disengages, separating the batteries. This system eliminates the possibility of draining the wrong battery and protects sensitive electronic equipment powered from the house battery from harmful engine start up spikes.

Decided to go with Supercharge Allrounder batteries.