It's not a simple answer.  There's WAY more to it than you might think!  Take a look at this NEW video!

 

 

Finally!  At last we are having that "tough conversation" about extension cords!  Great video and great topic.  I have a cabinet full of extension cords.  My boat has it's own 25ft 12GA.  My heavy draw power tools (table saw, pancake compressor, circular saw) all get 50ft 12GA.  You're absolutely right, people grab the "cheap" cord, but you get the power you pay for.  You can overheat your charger or power tools if you aren't delivering enough amps. 

I have a fairly short, heavy duty  extension cord only for my charger. I want to say it's around 15', no more than 20'. I leave my charger plugged in.

20 minutes ago, volzfan59 said:

I have a fairly short, heavy duty  extension cord only for my charger. I want to say it's around 15', no more than 20'. I leave my charger plugged in.

I purchased an extension cord specifically for the charger. 25', 10gauge...the NOCO has maintenance mode, so I leave it plugged in 24x7.

The starter battery I remove and put it on it's own charger, also with maintenance mode...no extension as it's parked right by an outlet.

When I built my lean to last fall for the boat, I purposely added an outlet for the charger. It’s about 6’ off the ground in the side of the barn, and when parked in the lean to it’s about 5’ from my onboard charger to the outlet. I have a 10’ 10g cord that is used only for the charger to the outlet, and it hangs on a hook beside it when not being used. I can sit in the boat and reach over beside me to plug it in as soon as I park it in there at the end of the day. I don’t leave mine on the charger 24/7, just plug it in when I park and unplug the next morning. 

I plug mine in after an outing, all my built in chargers have a maintenence mode, so I could just leave them plugged in.  But I don't, instead, after a couple days I unolug then monitor with a digital meter just in case.  If I know when my next trip will be, I plug back in the night or day before.  My batteries from my motorhome, side x side, mower, and other toys spend the winter on maintainers, and during the busy season they get charged when needed.  Must be doing something right as my batteries typically exceed average life expectencies by a bunch. As long as that happens I will keep doing what I do.

Although lithium batteries are excluded from the video, I think it's important to point out that you need to be careful about leaving them plugged in all of the time.  The reason being that you don't want to try to charge them outside of their normal operating temperatures.  You don't want to charge them above about 140°F, which sounds high, but if they're out in the sun on a hot day and heating themselves up from the act of charging, you can surpass.  Also, you don't want them to charge below 32°F or freezing.  On a good battery, the BMS will shut the battery down before those temperatures are met, but it's best not to test it if you can.  So it's okay to leave the battery on a lithium charger with a maintenance mode, but only if you're temperatures aren't going to be swinging into the extremes.  

 

Also, lithium or lead acid batteries both do best when stored at around 80% charge.  So if you're planning on not using the battery for a long time, it's better to take it off the boat and not keep it on a charger (even with a maintenance mode), but instead to top it off once a month or so, so it doesn't drop too far either.  However, if you are using the battery often, you want it to be fully charged when you're ready to use it, and it won't shorten the lifespan of the battery by that much to keep in on a maintenance charger, so that's a good compromise.  

I always thought my battery chargers were strongest when you first plugged it in and turned it on, but I just assumed I was crazy. Glenn you know way too much on way too many topics haha

I leave my battery charger on 7/24 since 2000. I bought a Ranger 185 VS in 2002 & it was a 3 battery boat. The boat was 35 feet from the outlet & had a built in 10 amp 3 bank Minn Kota charger. The extension cord is a 50 ft 12 gauge When I come off the lake the 1st thing I do is turn off the circuit breakers & plug the charger in. The batteries are the lead acid type & I would get between 5 & 6 years out of them. When Installing the batteries I put a brass washer on the post 1st. then the cables that are to be put on that post than another brass washer than the nut then some grease. I have found this works better than the pads you can buy to help with corrosion. I check the water once a month & once a week when the Temp. is 80 plus In 2008 I bought a Ranger Z-21 which has bulit in 15 amp 4 bank Minn Kota charger. When I change my car & truck batteries I do the same thing when installing them.

Excellent video Glen! 

 

Retired Dad / carpenter gave me a HUGE extension cord he used to run table saw with. This is my boat charger...and it stays plugged in 24/7/365. Boat is in my unheated shop all year.

 

Batteries are 3+ years old and still going strong.  

 

 

Side note: I use these for my John Deer x750, two Polaris 550's, portable generator, spare truck battery. Again, they are plugged in 24/7/365, and live in the unheated shop. 

 

 

 

 

 

@TnRiver46 Consumer deep cycle battery chargers are typically "Taper Chargers," meaning the current decreases as the battery's voltage and state-of-charge increase.  So yes, you are correct!  Once the battery reaches "full charge", the charger stops charging.

 

Note, this is not to be confused with "trickle charging", which applies a constant low current to the batteries. If you plan on leaving your batteries sitting for long periods of time, be sure to pay attention to the capabilities of your trickle charger. Some manual chargers simply emit a low amperage, but that’s about it. That means they don’t know when to shut off, and you can fry your batteries - or worse - start a fire. 

 

Smart trickle chargers, however, have advanced capabilities such as switching into “float” mode to keep your batteries topped off.

19 hours ago, scbassin said:

The batteries are the lead acid type & I would get between 5 & 6 years out of them.

That's pretty good lifespan out of a standard lead acid battery.  I got 4.5 seasons out of my previous deep cycles and 6 seasons out of my cranking battery before I had to replace them.  I don't leave my batteries plugged in 100% of the time, but I always fully charge them after each use.  In the winter time, I keep them topped off regularly while they are in an unheated garage.  My boat is also equipped with a master power switch to avoid any unnecessary drainage.

I’m running lithium but also ran agm’s for years. Charger plugged in 24/7/365 on Minn Kota precision. Stored in temperature control garage but also the extension cord is 8’ long and is a gfi. I never plug my boat in without a gfi.

Several boats over the past decades and several different types of chargers and batteries. 

The best wet lead acid battery for me back in the 80’-90’s was Trojan SC 225’s with a watering system and  unplugged the charger when fully charge, batteries lasted about 5 years.

When AGM’s came out around 2005 bought a smaller Boat with onboard NoRCo Genesis 3 pro charger and VMax AGM’s and still unplugged the charger when charged, just didn’t fully trust the charger. Sold the boat in 2021 with original batteries and the buyer is running them! Don’t know if he unplugs the charger?

Tom

PS, 2 gr 31’s and 1 gr 27 for cranking-electronics.

 

I sleep better at night if I unplug the chargers, even though the 3-car garage is not attached to the house. I don't trust chargers or batteries and only takes a few hours at most to charge anything I own. And forget wet cell, I love how fast the 3-bank Minn Kota PC charges my 3 Duracell Group 31 AGMs.

 

There's a lot of stuff in garage and the unfinished walkup attic. I could easily replace the 16-foot boat, the 48" Deere X380 and the Toro MX5050 zero turn, but I would never hear the end of it if my wife lost all of her old stuff and her son's stuff and their old baby furniture, etc.,etc.,etc. 

Alot of good info right here