Alternative to a deep cycle battery

[Tom L.]

I was wondering if anybody has tried to uses one of those jump start batteries as a boat battery. I am thinking about it because I do not have 110 power for a charger where I store the boat. I would need to lift a battery out of the front storage area and lug it ashore.

My power consumption is very low. We sometimes stay out for two or three nights. Seldom use power except for the sounder and a cabin light. We use tap lights in the cabin most of the time and have a dry cell powered anchor light.

I was just wondering if a jump start battery would be usable. It sure would be easier to take back and forth to the boat when we wanted to cruise a few days. I think they have a built in charger to plug in to 110?  They are available at Harbor Freight for a very low cost.

[Salty19]

Yes, I think they would be just fine and would work for your needs.  12V is 12V and it doesn't sound like you'll be pulling much in the way of amps (load) to justify a heavy, high capacity marine battery.  LED bulbs in the cabin would save even more power.

On another note, I'm using an "Odyssey" heavy duty AGM Group 31 size auto battery.  Odyssey's are nice batteries- keep their charge well and put up with abuse (read low charge) really well.
I charge it once in May and don't worry about it untiil fall haul out.  I run all LED lights and do sail at night several times a year. The LED's barely use any capacity..my voltmeter barely blinks at them.  
Like you, I use flashlights more than the cabin light, but it still gets use. I forget how many amps the battery it is but I think over 900...it is not small task to get it off the boat while on a trailer!
So I can't blame you for wanting something easier to deal.

I am considering using a very small (UPS type, similar to batteries in commercial "EXIT" signs with fire lights) 12V AGM battery--just a few pounds of spillproof amps that would be easy to take home and charge it once a month.
I barely use any power and being on a small lake, it's not like I'm going on an extended voyage or "need" power.   Would certainly remove a ton of weight and add a lot more storage.  

Anyway, the UPS battery might be something to think about as an alternative if you have low demands on your power system.  

[FireDrill]

I use one of the jump start batteries regularly as back-up to my conventional deep cycle battery on my SunCat.  Once I had a connector problem with the deep cycle and used the jump starter for three consecutive day-sails -  It basically powered my GPS-Depth sounder full time for all three, ran some cabin lights for an hour or so, and charged a cell phone for a half hour  Kept it in battery chamber in bow locker to port of deep cycle battery and mast stub.. When I took it home to recharge it,  I was surprised it was still about 50% charged. Mine was from Advanced Auto, PEAK brand 2nd from top in price/features (900 Peak Amps) .  West Marine has their own brand $80-110 300 and 600 Amp 12 and 15.5 Ah respectively.     

Mine provides all the qualities you mention and I've often thought two of these would do just fine on my Suncat without the deep cycle. I always like the idea of having a backup battery so I'd suggest 2.    However two would be about the same total space as a small deep cycle but you have the portability for recharging and space saving by virtue of stowing two smaller packages in separate places if desired.  Recharging is simple - just pug it in to any extension cord. I'd keep rotating which one I'd take home to charge, keeping one on the boat at all times - just in case you forgot to return with the charged one.  Most of these units  have several additional features the deep-cyle does not have:  charge status meter, USB charging port, built in light, low charge alert, built in 12 volt accessory port (cigarette lighter socket) Some even have alternator for 110 AC or an air compressor (for that inflatable dinghy.   Also useful if tow vehicle needs a jump start!

I have read an account, I think  in Small Boat Journal approx. 2 years ago - about a microcruiser that used one as the standard  single power source for a several day trip but do not recall details. Think it was a Wagen-Power Dome EX (also in West marine catalog)  with the 110 AC inverter, AM FM radio, audio input for ipod etc 

So go for it.. I think it will work just fine for your purposes!
 

[capt_nemo]

Tom L.,

YES, a Jump Start Battery will satisfy your needs. Especially if you try to use small batteries to power most of your other lights and accessories requiring electricity.

I do not have a Deep Cycle Battery or installed electrical system and running lights aboard my Sun Cat and have spent several days cruising and anchoring out using small battery powered lights and accessories. Carried a Jump Start Battery and small 300 Watt Inverter just in case I had to recharge my cell phone 'cause I had to check in with my wife periodically to assure her I was still alive and OK!

Strongly recommend keeping your electrical requirements reasonable and the "system" to satisfy them as SIMPLE as possible.

capt_nemo

[Tom L.]

I am convinced based on the positive comments about the Jump Starter. The battery in place right now is shot. The cost of a jump starter is less than just a battery plus I would need a charger. In addition I would have to carry the battery home to recharge. All good in my opinion. So it's off to Harbor Freight for the 900 peak amp 3 in 1 package. I have a coupon for $37.99.

Thanks
Tom

[hoddinr]

Hi Tom,

I went to Sears several years ago and got the top of the line Jump Start Battery.  I have replaced the internal battery in it at Batteries Plus once.  It has a built in inverter for 110 plugs as well as the 12 volt cig lighter plugs - other features - light and tire pump have come in handy a few times. 

I'd be careful buying at Harbor Freight. 

Ron

[relamb]

When I bought my CP27 the battery was pretty bad, and didn't seem to take a good charge.  Probably because there was nothing connected to the "Battery Charger" breaker, it didn't have a charger!  I bought the top-of-line portable jumpstarter at Walmart Schumaker brand, which had a power inverter, lighter sockets, and air pump built in, for around $100.  It also has a feature to show how much current is being drawn as it operates, as well as how much of the charge remains.
I used it for several days until I was able to get new batteries. It will jumpstart the diesel in the CP27.  Even now I keep it charged up on the boat, use the inverter function, and don't worry about running down the boat batteries because I can always use it for a jump start.   I made a double ended cord with two cigarette lighterplugs (per the manual) , and you can charge the device back up from the boat batteries or a car, connecting socket-to-socket with the cord.
One thing I did determine, setting it in the car to charge from the car battery will only charge it half way.  The car needs to be running to get the voltage high enough to charge it to full charge.  So letting it set in the car overnight didn't do a lot, I had to charge while driving, or  from 110v.
I'm considering buying a second one for my wife to keep in her car, and to use while camping.

[Tom L.]

Hi Ron, Didn't know who you were at first. I am skeptical about the H.F. equipment too but it is very inexpensive, $37.00 with a coupon so I think I am going to give it a shot. I don't need the compressor as I carry a very good one form my RVing days.

BTW I got a line on a used 78SC which as you know is dry cell battery operated so I need even less power from the boat battery.

I can't believe it but here it is prime sailing season and I have to go back North for the Holidays...Bah-Humbug. Hope to see you in Mid Jan.

Tom L.

[reedtg3]

Greetings, Guys-
A jump start battery is good to have on board.  I carry one as a back-up power source for my cpap machine.
Tom / Cattail