Adding a 2nd battery?

[LCT]

Did you cut the mount for the WDH or lay the angle iron on top?

[thenne1713]

Originally Posted by Finally Able

Hi, new to the forum, with a 2021 287 BHS which we have enjoyed a few times at sites with full hookups. This is our 1st TT. We lent it to my daughter and her family yesterday for weekend -- I dropped it off at a NH state park CG with no hookups. I told them of the importance of being mindful of trailer resources (water, LP, DC power) when dry camping.

Anyway, I got call this a.m. saying battery is dead -- fridge and water heater were on LP setting, LED backlight on stovetop dials left on as nightlight for young children. They also used the radio for a couple hours.

Though I haven't dry camped (at least with access to such luxuries!) I'd have thought the battery would have carried them further. I realize there are inherent draws (appliances mentioned, LP leak detector, Furrion entertainment system on standby mode whenever not in use, etc.)

1. Am I right or wrong? and
2. Should I install a 2nd battery? and
3. How can this be avoided in future in terms of power management?

Many thanks for any replies.

(and [they] probably left trunk lights on too? LOL :-) ) but also battery connections MUST be bright/ shiny and battery 100% charged to survive dry camping without recharge? Even SLIGHT terminal corrosion can STOP battery from charging over about 70%. They brought no GEN? or did not run evening before bed? WHAT did you/ they expect? (MY RULE) is expect MIN 4-HRS GEN run/ day? Little over 1-hour each meal time? Short at Bedtime.

[eagle55]

Originally Posted by LCT

Did you cut the mount for the WDH or lay the angle iron on top?

The new battery rack has (4) pieces of pipe (actually square stock but pipe works too) as spacers. These spacers are used to bolt directly to the old rack with 1/2" by 6" (if I remember) carriage bolts down the inside of the spacers and none of the new rack rests on the tongue although they are within a 1/4 inch or so. The old rack is plenty strong supporting the new one like this even with 2 batts.

[LCT]

Thank you. Looks very good

[Finally Able]

Originally Posted by eagle55

As part of the package I negotiated from the dealer was to have (2) new deep cycle batteries which I got. Unfortunately they could not install the second battery because there wasn't enough space between the A frame tongue. So when I got home with the trailer I built a raised battery rack out of (2) pieces of 1-1/2" angle steel.
If you are interested, here are some photos of how I expanded the space for batteries by raising them up on top of the tongue. Looking at photos of your model it could be that you will run out of room for a second battery just as I did. Note I did do a bit of welding to make the rack, but you could probably get by with carriage bolts. Also I don't advise welding directly to the tongue.

Nice job! I'm holding off on any battery upgrade decision until next year, so I'll keep that idea in mind should I need it -- thanks.

[Finally Able]

Originally Posted by thenne1713

(and [they] probably left trunk lights on too? LOL :-) ) but also battery connections MUST be bright/ shiny and battery 100% charged to survive dry camping without recharge? Even SLIGHT terminal corrosion can STOP battery from charging over about 70%. They brought no GEN? or did not run evening before bed? WHAT did you/ they expect? (MY RULE) is expect MIN 4-HRS GEN run/ day? Little over 1-hour each meal time? Short at Bedtime.

No generator (well, they borrowed one later in the day.) It's a brand new TT and battery, and I've been around long enough to know that electrical connections must be clean, bright and tight, which they were. Dunno what you mean by trunk lights. As to what we expected, I/we had no idea, as this was the 1st experience dry camping. Now I know a bit more, thanks to folks who responded to this thread. Their power usage was minimal, but if added to background power draws and smallish battery...

[videoarizona]

Will Prowse is very good. Knowledgeable young man. I like him.

I went with 2 6 volt golf cart batts. GC2. An honest 100amps. The only issue with 2 6 volt batteries is if one dies, you are dead in water. Golf cart batteries are true deep cycle so you can discharge them down below 50%.

Next year I'm going to upgrade to 2 12volt Battleborn lithiums. 100 amp each. Total usable will be 200 amps, as lithiums maintain full output until they die. Reason is, I can discharge them down to near zero capacity and no damage. Excellent for boondocking. I also bought a 100 watt Renogy suitcase solar panel and controller... And a Honda 2200 generator. I changed all lights to leds. Added the Easy Start to my AC so I can run off the small generator. And Hutch Mountain's propane conversion for the Honda so I can run gas or propane. I've gone as far as I can with my trailer. No more room for a battery bank. And can't afford a large solar array on the roof. But I'm good for an easy 3 days. Can stretch to 4 without cranking the generator. I'm pleased.

As had been said, this is a personal quest. You have to decide how you will use the trailer. Then start making the $$ decisions to equipt your trailer to your needs.

You might also think about a battery disconnect switch to isolate battery from coach. This will save battery during down time. And maybe some on/off switches to shut off the equipment that has parasitic draw.

I've enjoyed the learning process. It's fun, actually!

david
PS. The only true measurement of the capacity of a battery is rated at the 20 amp/hour rate. This is the industry standard. Most batteries are not rated at that discharge rate. Or at any rate! Some manufacturers use a computer to simulate. Really? Any battery you settle on should be rated by the above. That gives you the true amp capacity of a given battery.

[Finally Able]

Originally Posted by videoarizona

Will Prowse is very good. Knowledgeable young man. I like him.

I went with 2 6 volt golf cart batts. GC2. An honest 100amps. The only issue with 2 6 volt batteries is if one dies, you are dead in water. Golf cart batteries are true deep cycle so you can discharge them down below 50%.

Next year I'm going to upgrade to 2 12volt Battleborn lithiums. 100 amp each. Total usable will be 200 amps, as lithiums maintain full output until they die. Reason is, I can discharge them down to near zero capacity and no damage. Excellent for boondocking. I also bought a 100 watt Renogy suitcase solar panel and controller... And a Honda 2200 generator. I changed all lights to leds. Added the Easy Start to my AC so I can run off the small generator. And Hutch Mountain's propane conversion for the Honda so I can run gas or propane. I've gone as far as I can with my trailer. No more room for a battery bank. And can't afford a large solar array on the roof. But I'm good for an easy 3 days. Can stretch to 4 without cranking the generator. I'm pleased.

As had been said, this is a personal quest. You have to decide how you will use the trailer. Then start making the $$ decisions to equipt your trailer to your needs.

You might also think about a battery disconnect switch to isolate battery from coach. This will save battery during down time. And maybe some on/off switches to shut off the equipment that has parasitic draw.

I've enjoyed the learning process. It's fun, actually!

david
PS. The only true measurement of the capacity of a battery is rated at the 20 amp/hour rate. This is the industry standard. Most batteries are not rated at that discharge rate. Or at any rate! Some manufacturers use a computer to simulate. Really? Any battery you settle on should be rated by the above. That gives you the true amp capacity of a given battery.

Good info, many thanks! I'll be spending some downtime this winter learning what I can; this is helpful.

[videoarizona]

Welcome. I'm from Portsmouth. Grew up in NH. Loved it there..... But the sunshine in Arizona was to inviting!

Get a clamp on meter. I got mine at Sears on line for less than $100. Small too. Can measure amp draw easily. As well as be an accurate voltage meter.

1st though is make sure all interior lights are LED. Should be with a new trailer.

Holler if you need anything else over winter..
David

[videoarizona]

https://m.sears.com/craftsman-cm/p-A028382415

[Finally Able]

Originally Posted by videoarizona

Welcome. I'm from Portsmouth. Grew up in NH. Loved it there..... But the sunshine in Arizona was to inviting!

Get a clamp on meter. I got mine at Sears on line for less than $100. Small too. Can measure amp draw easily. As well as be an accurate voltage meter.

1st though is make sure all interior lights are LED. Should be with a new trailer.

Holler if you need anything else over winter..
David

Thanks, David! Lifelong New Hampshirite myself. I've always loved Portsmouth/Seacoast. We are camping presently in Kennebunk ME. Hope to make it out to AZ in next couple years to see the sites. And thanks for the clamp link. (Yes, all lights are LEDs.)

[captainbrad1029]

The issue with adding a second battery is that if they are simply wired in parallel they are likely to suffer a shortened lifespan. The charger sees them as one load and if one of the two batteries is weak it will continue to charge and overcharge the other, damaging it’s capacity. The process repeats until both are essentially worthless. There are two ways to prevent this. Either install a battery switch and charge and use them one at a time or install a dual bank battery charger (available from marine stores). I went with the switch option and installed a marine battery switch. (See photos)

The other option, and probably honestly the easiest, it to get a Honda (or similar) ultra quiet suitcase generator and run that during the day with the TT plugged into it. That’ll top up the battery, allow everyone to charge their devices, and cover all the kids during the day. Those gens usually won’t run the air but you wouldn’t have that boondocking anyway so not really a loss.

[eagle55]

Originally Posted by captainbrad1029

The issue with adding a second battery is that if they are simply wired in parallel they are likely to suffer a shortened lifespan. The charger sees them as one load and if one of the two batteries is weak it will continue to charge and overcharge the other, damaging it’s capacity. The process repeats until both are essentially worthless. There are two ways to prevent this. Either install a battery switch and charge and use them one at a time or install a dual bank battery charger (available from marine stores). I went with the switch option and installed a marine battery switch. (See photos)

The other option, and probably honestly the easiest, it to get a Honda (or similar) ultra quiet suitcase generator and run that during the day with the TT plugged into it. That’ll top up the battery, allow everyone to charge their devices, and cover all the kids during the day. Those gens usually won’t run the air but you wouldn’t have that boondocking anyway so not really a loss.

You bring up some good points, but I would like to respectfully rebut a bit of it. While it is true that if you use 2 different batteries, or even 2 exactly the same but different condition/age, the one will bring down the other. But there is a way around this. If you are going to use (2) 12v, in parallel, or even (2) 6v on series, buy and install identical batteries at the same time, and this should eliminate most issues with a weak cell. And another thing along the same lines is that I have found that having a way to give a battery a few hours of "equalize" charge every so often also keeps all cells at the same condition over years of use. Equalize charge would be around 14.4v where a float is usually 13.7v. When you tow your trailer, the tow vehicles alternator automatically charges at around 14.4 to 14.6 so every time you drive somewhere your batteries are getting an equalize charge.

However, some coach 110v chargers don't seem to do an equalize charge, at least maybe not often enough and cells can start to vary in their individual voltage. This year I installed a Renogy rooftop solar system with a MTTP charge controller, and that controller does a 2 hour "boost" charge every day the sun is out, and during that time, brings the voltage up from 13.7 to 14.4v. This is all it takes (if the batteries are identical and both purchased at the same time).

I highly recommend for anyone who does off the grid camping to get at least a 100w solar panel (200 or more is better) and a good quality mppt controller that does regular boost or equalize charges. What tends to happen otherwise is when having to run the generator, it takes a long time to FULLY recharge a battery. The problem is that last 10% takes the longest, and while most people will charge to what appears to be 100% on the gauges, it really is not. A hydrometer , or perhaps an amp hour meter, the type that shows amps going back into the battery is the only way to truly tell (other than leaving it plugged into shore power for many hours) if you are getting a full recharge. That is where the rooftop solar panels do such a good job for boondockers, as they work all day at charging that last 10%, and all without the noise and fumes.

[Finally Able]

Originally Posted by captainbrad1029

The issue with adding a second battery is that if they are simply wired in parallel they are likely to suffer a shortened lifespan. The charger sees them as one load and if one of the two batteries is weak it will continue to charge and overcharge the other, damaging it’s capacity. The process repeats until both are essentially worthless. There are two ways to prevent this. Either install a battery switch and charge and use them one at a time or install a dual bank battery charger (available from marine stores). I went with the switch option and installed a marine battery switch. (See photos)

The other option, and probably honestly the easiest, it to get a Honda (or similar) ultra quiet suitcase generator and run that during the day with the TT plugged into it. That’ll top up the battery, allow everyone to charge their devices, and cover all the kids during the day. Those gens usually won’t run the air but you wouldn’t have that boondocking anyway so not really a loss.

Thanks -- as to the generator, I've heard good things about Harbor Freight knockoffs being equally as good as Hondas, at 1/2 the price. We aren't planning on boondocking anytime soon, so will hold off on any purchase. Any thoughts about HF gens?

[captainbrad1029]

Originally Posted by Finally Able

Thanks -- as to the generator, I've heard good things about Harbor Freight knockoffs being equally as good as Hondas, at 1/2 the price. We aren't planning on boondocking anytime soon, so will hold off on any purchase. Any thoughts about HF gens?

I’ve heard that as well. No direct experience but I use a lot of their other stuff and the quality has certainly improved over the last ten years! I imagine there are some posts in here WRT HF gens.

[captainbrad1029]

Originally Posted by eagle55

You bring up some good points, but I would like to respectfully rebut a bit of it. While it is true that if you use 2 different batteries, or even 2 exactly the same but different condition/age, the one will bring down the other. But there is a way around this. If you are going to use (2) 12v, in parallel, or even (2) 6v on series, buy and install identical batteries at the same time, and this should eliminate most issues with a weak cell. And another thing along the same lines is that I have found that having a way to give a battery a few hours of "equalize" charge every so often also keeps all cells at the same condition over years of use. Equalize charge would be around 14.4v where a float is usually 13.7v. When you tow your trailer, the tow vehicles alternator automatically charges at around 14.4 to 14.6 so every time you drive somewhere your batteries are getting an equalize charge.

However, some coach 110v chargers don't seem to do an equalize charge, at least maybe not often enough and cells can start to vary in their individual voltage. This year I installed a Renogy rooftop solar system with a MTTP charge controller, and that controller does a 2 hour "boost" charge every day the sun is out, and during that time, brings the voltage up from 13.7 to 14.4v. This is all it takes (if the batteries are identical and both purchased at the same time).

I highly recommend for anyone who does off the grid camping to get at least a 100w solar panel (200 or more is better) and a good quality mppt controller that does regular boost or equalize charges. What tends to happen otherwise is when having to run the generator, it takes a long time to FULLY recharge a battery. The problem is that last 10% takes the longest, and while most people will charge to what appears to be 100% on the gauges, it really is not. A hydrometer , or perhaps an amp hour meter, the type that shows amps going back into the battery is the only way to truly tell (other than leaving it plugged into shore power for many hours) if you are getting a full recharge. That is where the rooftop solar panels do such a good job for boondockers, as they work all day at charging that last 10%, and all without the noise and fumes.

I agree on all points, at least in the theoretical. What I don’t know (I’m no battery expert or electrical engineer) is if the cells can eventually develop differences (also theoretical I suppose). In my case I don’t always have a second battery on the TT. I grab a deep cycle out of my boat when we’re going boondocking so they are never going to be exactly the same WRT lifespan. The other thing I like about the switch is along the lines of the propane tanks where you have the option to run it as a primary and reserve.

I would like to do solar at some point. My biggest concern is mounting the panels to the roof in a way that’s strong enough to not move at highway speeds and also remain watertight (I’m in MI so winter snow and seasonal temp swings are a factor). Haven’t really started going down the rabbit hole of solar research yet.

[eagle55]

Originally Posted by captainbrad1029

I agree on all points, at least in the theoretical. What I don’t know (I’m no battery expert or electrical engineer) is if the cells can eventually develop differences (also theoretical I suppose). In my case I don’t always have a second battery on the TT. I grab a deep cycle out of my boat when we’re going boondocking so they are never going to be exactly the same WRT lifespan. The other thing I like about the switch is along the lines of the propane tanks where you have the option to run it as a primary and reserve.

I would like to do solar at some point. My biggest concern is mounting the panels to the roof in a way that’s strong enough to not move at highway speeds and also remain watertight (I’m in MI so winter snow and seasonal temp swings are a factor). Haven’t really started going down the rabbit hole of solar research yet.

Definitely in your situation, if you are mixing batteries from your boat and RV at different times, even if they are the exact battery I would keep them isolated with the batt switch as you suggest. The only time I would parallel 2 batteries for overnight discharge (anything that doesn't have a charger of some sort applied) is if they are always the same batteries in the coach. When paralleling, or series 6v only if you pair 2 identical batteries, bought at close to the same time preferably, so all cells are kept in more or less identical condition, and then apply an equalize charge once every so often, monthly, weekly etc will you have the best result.

Where I live, there are a lot of boat people, and when asked about separating batteries, I tell them the same thing, separate unlike batteries, such as the battery that starts the engine, from the batteries used for overnight lights, and what have you. Only time would one keep the battery selector to both (A+B) is when running the boat engine, where the alternator is putting out an equalize charge, 14.5v to both in which case all cells will be taking the same charge. Its no different from a travel trailer in that when driving down the road the coach battery and the truck battery are paralleled. But when stopping for the night, its best to unplug the truck from the trailer. Not only will that insure the truck battery won't be going dead enough not to start the engine the next day, but due to their big differences in the cells between the deep cycle batteries in the coach and the battery in the truck being made for cold cranking amps, disconnecting them keeps them from pulling each other down.

I hear you about mounting the solar panels on the roof! I did mine this spring, and have no sign of leakage. I used a stud finder to find the roof trusses, and its a bit tricky in that you can't know what the layout is. Mine seemed to be placed wherever, and not on a 24" center. Once I found the trusses I was able to position the clips where I could sink hefty screws into the wood. Then I used the RV self leveling roof product. So far so good, but I am going to be checking the area at least once a year for any sign of cracks etc..

As for rooftop solar, I like to have a few hundred watts up there, always charging even on cloudy days, but I also l like to have a suit case panel for days when I'm camped out under the trees. If I had to have just one, I would go with the rooftop as they are always setup and working..

[1SGPETE]

Originally Posted by Finally Able

Hi, new to the forum, with a 2021 287 BHS which we have enjoyed a few times at sites with full hookups. This is our 1st TT. We lent it to my daughter and her family yesterday for weekend -- I dropped it off at a NH state park CG with no hookups. I told them of the importance of being mindful of trailer resources (water, LP, DC power) when dry camping.

Anyway, I got call this a.m. saying battery is dead -- fridge and water heater were on LP setting, LED backlight on stovetop dials left on as nightlight for young children. They also used the radio for a couple hours.

Though I haven't dry camped (at least with access to such luxuries!) I'd have thought the battery would have carried them further. I realize there are inherent draws (appliances mentioned, LP leak detector, Furrion entertainment system on standby mode whenever not in use, etc.)

1. Am I right or wrong? and
2. Should I install a 2nd battery? and
3. How can this be avoided in future in terms of power management?

Many thanks for any replies.

I had the same problems, with the battery going low or dead. I added a second one while out at Quartzite a year or so ago. It works beautifully. I plan to add a third as son as I get to it.
My wife likes to run the power vent at night when we boondock and it will not last all night long.
We run the generator in the evenings to make supper and to watch a movie before bed. Then I turn it back on for coffee in the morning. WE leave everything plugged in that we want to have charged for the next day and this works fine for us I feel that a third battery will insure we don't run the battery power out and shorten the life span of all three batteries.

[IamSpartacus]

Before getting another battery, think about where and how you'll be camping because that will drive you towards certain setups. If weight is not an issue I would grab 4 6 volt from Sam's club and then solar it up (youd be looking at 450 amps of usable power, 900 total). Weight was a serious issue for me, I did not want to install solar yet, so I went lithium. It did require some wiring changes and a new converter but I set it up so that the future solar install will be much easier. What I found was that charging the batts was so fast though, I may not install solar after all. Good luck.