Charge starting battery through lighter receptacle?

[agrazela]

Hey all,<br /><br />I want to know if it would be possible to charge the starting battery on my boat through the cigarette lighter receptacle.<br /><br />Here's the situation:<br /><br />I have a popup tent trailer that I park right next to the boat. The popup has an IntelliPower onboard charger with the Charge Wizard do-hickey; it does a great job charging the AGM "house" battery in the popup. I wired external, weatherproof lighter-type receptacles on the popup for cooking with 12v appliances while camping.<br /><br />Can I craft a cord with a lighter receptacle plug at each end to go between the popup and the boat and use it to charge my lead acid boat battery?<br /><br />Would I have to unhook the popup's AGM battery to do this? What gauge wiring and fuse amperage would I need in all the circuits (I wired all the receptacles with 10 AWG and use 15 amp fuses)?

 

[cuzner]

Re: Charge starting battery through lighter receptacle?

I think you can do it. I use a fairly large solar panel on my boat to charge through lighter socket. Its designed to work that way.As far as gauge of wire All I can suggest is use smallest gauge you fit in set up.Someone else can probably help you more in this area than me.<br /><br /> Jim

 

[18rabbit]

Re: Charge starting battery through lighter receptacle?

If wired correctly, it's do-able. If wired incorrectly, could cause a fire. Use appropriate conductor(s) and over-current protection.

 

[Paul Moir]

Re: Charge starting battery through lighter receptacle?

Another thing to watch out for -<br />Automatic chargers watch the battery voltage very closely while they're charging, and decide on which part of the charge profile they'll use based on tenths of a volt. If the connection is well made, then it's no problem. But if the connection is a little corroded or dirty, the charger is going to get confused.<br />So make sure your lighter socket and plug is very clean if you charge this way.

 

[ndemge]

Re: Charge starting battery through lighter receptacle?

...Lighter Socket usually only fused at 15 amps, so make sure your charger doesn't put out more than 15 amps. If it does, you need to wire up another higher amp rated receptical to plug everything together.<br /><br />You might want to do this anyway, if someone tripped over that cord, it could rub something metal and start a fire.

 

[BF]

Re: Charge starting battery through lighter receptacle?

It might work, but I'm not sure having a cord with 2 male ends is a great idea. When you plug one end in, the other end has 12 volts on it's exposed contacts. It could dead short pretty easily (wet hands, or drop it on something conductive). It would also be very easy to dead short it while plugging it into your boat if you touched the tip of the cord to the outside of the boat's lighter socket.<br /><br />Putting a switch in the cord would help I guess. At least you could keep the boat end dead until you get it all connected.