Lithium battery for yak

[SWVABass]

I have a 2019 Hobie pro angler. Looking to move to a lithium battery for running my electronics. Right now I have a lowrance hook revel TS 7”. I would like to add led lights for rigging pre sunup. Also would like to add a charging port for a phone. 
 

can anyone give some input on how many amp hrs I should be looking at. I have been thinking about two nacqua power kits, and the Viking hatch to replace my rear hatch. Would this set up work?

[Bass Junke]

I have everything on my kayak you are talking about. I am using a 12 ah LiFe Po battery. I have used it for roughly 10-11 hours still does not need to be charged. 

I have red/green light in the bow, white lights in the stern, a pair of red cabin lights, a removable 360 degree white light, a hookup for sonar, and an amp meter with 2 USB ports. The 12ah battery runs it all without much of a drain. LED lights use very little power, and that is really all we are talking about, sonar and a bunch lights that all aren't going to be on at the same time anyway. 

I have an old 7ah lead acid battery that will run my system all day. 

 

I do not know what you are talking about in your second paragraph. I do not have a Hobie and I am not familiar with the other products. 

[CountryboyinDC]

I've seen the hatches with the Noqua battery hangers - I think they're the Vikings you referenced.  With 1 10ah Noqua, I can run a 7" Lowerance HDS Carbon with a Totalscan transducer all day (8+ hours).  As for the phone and lights you'll have to figure your draw for them.  I know the LEDs don't draw much.  2 AA batteries power my little Yak attack flag/light combo overnight for a couple of nights.

The hatch replacement/dual Noquas would be a tidy way to go about it, maybe not the least expensive.

[Darth-Baiter]

The sweet thing about the nocqua battery is the Velcro flap.  I simply wrap the flap around the inside tube the sail kit stabs into.  It’s inside my front Hobie hatch. No need to buy that kit to store batteries.  
 

the thing about the Nocqua dual battery setup. It doesn’t run the batteries in parallel or anything. It runs down one battery to a predetermined level ( I was told 10.8 v) then it automatically switches it to the other cell. 
 

I can run my hook5 reveal for around 10 hours. I have two nocqau batteries for multiple day trips.  They do require a thoughtful approach to charging. 
 

if I did it again I would get the 17ahr battery that guy sells on a kayak forum.  About $180. Cheaper than two nocqua units. 

[Guest]

Hey guys thanks for the input I appreciate it. Reason for looking at the rear hatch was to try to move some weight to the rear end. I have seen how they attach to the sail mount @Darth-Baiter.

 

@Bass Junke where did you pick up the amp meter/charger? 

[Bass Junke]

Volt meter, sorry my mistake. Something like this. Purchased from Amazon. 

[DogBone_384]

Do you use any 12V power tools? I power my Lowrance Hook-5 with Milwaukee M12 batteries, stowed in a Pelican box with a quick-disconnect.  I get almost two full day trips from a 6.0 AH XC.

The Pelican box holds two XC batteries while fishing and keeps the control head safe when I’m not fishing.

[Bankc]

With a lithium battery, it will read a near constant voltage until it is dead.  So a voltmeter or ammeter won't tell you anything other than what the battery is doing at the moment.  That's unlike a lead acid battery, which will gradually lose voltage, so you can estimate how much time you have remaining based on it's resting voltage. 

 

What you need for a lithium battery is a power analyzer, sometimes called a watt meter.  Something that reads the amount of current and voltage that passes through the device and measures it against time.  That will tell you how many amp hours you have used, and from there, you can subtract it from your batteries capacity to estimate how much power is left.  Be careful, as many aren't waterproof, so you'll need to waterproof it yourself.  Though, if you just get a battery that has more capacity than you'll ever use, then you don't really even need that.  Just make sure it's charged before going out.  

 

But if you're getting a combo voltmeter/USB port just for the USB connections, then that's fine.  The voltmeter itself won't consume a meaningful amount of power, so it won't hurt anything to have it.  Just don't rely on it for telling you how much power is left.