Welcome to TeardropForum.com Forums Teardrop Builders’ Forum Anyone using 12v lithium battery?

This topic contains 26 replies, has 9 voices, and was last updated by  Volund 2 weeks, 2 days ago.

Viewing 15 posts - 1 through 15 (of 27 total)
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  • #1220

    faithie999
    Participant

    On the maiden voyage today, the epoxy  joint between the galley flat and bulkhead failed under the vibration and weight of the 12v deep cycle group 27-size battery.  I have a plan for repairing and reinforcing the joint but now I’m thinking about buying a lithium battery.

    Any experience/advice?

    thanks

    ken

    #1221

    mpilone
    Participant

    Ugh, that really stinks. I started to look into battery options and lithium ion is really expensive in any reasonable size. Like 5 to 10x more expensive than lead acid. I was thinking it might be nice to use a few smaller lithium batteries with an easy way to swap them out. So for a weekend trip maybe get by with one or two and rotate them. Something like: http://amzn.to/2ikNrBI

    Another option is to mount the battery on the underside of the trailer as others have done. You’ll need to figure out how to waterproof it and protect it from road debris but at least it would be putting stress on the flat.

    Slightly off topic, this is at least the second galley flat failure I’ve seen in the forum. I noticed that in the latest Waterlust build video it looked like they glassed the flat. I don’t recall seeing that in the manual but now I’m thinking that at least tape on the inside seams would be a good idea if not glassing the entire flat and bringing it up a few inches on the sides and back. Thoughts?

    -mike

    #1222

    faithie999
    Participant

    I know that friz mounted a sealed AGM battery under the cabin.  The battery he used looks like it has a rugged case.  But then I’d need to decide where to drill holes to get power from the charger to the battery and from the battery to the distribution panel.

    In retrospect, you could glass the outside corner between the forward edge of the flat and the forward face of the bulkhead, before the shelf is installed.  I don’t want to do that now. What I will do is re-glue (thickened epoxy) the joint then screw a 1×1 piece of hardwood onto the bottom edge of the flat into tie bulkhead.  I’ll use #6x 2″ screws and work hard to make sure the pilot hole is in the center of the 3/8 bulkhead plywood, and dip the screws in epoxy before screwing them in.  The bulkhead plywood won’t hold the screws real well, but if I use enough screws it should hold.  I will also put some kind of floor in the galley module which should help to spread the force of the vibration from the 60# battery.  As a belt and suspenders approach I will use a scissor jack in the cabin to support the joint during transport.

    it’s possible that the joint failed because I wasn’t able to properly weight the galley flat when I initially glued it to the bulkhead (when it was still upside down).

    #1225

    friz
    Participant

    I’m sorry to see that this happened to someone else. The galley is definitely a week point on this camper. I have my battery mounted under the floor and had my galley loaded with normal camping stuff. A cooler and a 5 gal water jug which weighed much less then my battery and had the weight dispersed over a larger area. I though I was safe. This winter I plan to reinforce that seam with a tape on the inside. I will still load the galley lightly in the future. It is disappointing that the galley floor is so weak. You loose a lot of utility having to load lightly.

    #1226

    ArtisticAdam
    Participant

    Was your battery secured to the galley floor or just resting on it? This unfortunately seems to be a recurring problem.

    If you don’t mind a few bolt heads on the cab side of the bulkhead wall or can hide them behind a TV screen, I would recommend a simple solution by bolting it directly to the bulkhead with a bolt in battery box. (See Image Below)

    If you have the money Lithium is a great choice. There are many more reasons Lithium is superior besides being 1/3 the weight.

    https://www.powertechsystems.eu/home/tech-corner/lithium-ion-battery-advantages/

    Have you calculated your required Amp hours? If you really do need a 12v 100AH battery it’s likely a Lithium battery would cost you $600-$800

    CLC_Battery_Mount

     

    #1227

    comccoy
    Participant

    As you are not supposed to discharge lead acid batteries below ~50-75% if you calculate needing a 100AH traditional battery would it not make sense to get a 50AH Lion? This is my plan as I have seen them on sale for $350 with a charger included. If we end up needing more power than that I figure I can easily add a second as a backup.

    When I look at the other benefits to me it makes sense.

    • ~1/2 the $ or less over the life of the battery compared to Lead Acid
    • Zero maintenance
    • 1/3 weight and 1/2 the size of lead acid (even less for 50AH)
    • 100% discharge safely
    • Significantly longer life (some say 10x the 500 charge cycles of lead acid but more like 4x-5x with noticeable AH drop after that)
    • If sealed properly no gas expelled.
    • LFP is not the same as your cell phone battery that “explodes” with violent flames and seems fairly safe
    • There are versions that are drop in replacements for lead acid that can use the same charger etc you already have

     

    #1228

    faithie999
    Participant

    adam–interesting battery holder.  i’m a little skeptical about hanging 60 lb. from the 3/8 plywood bulkhead.  sure wish CLC had chosen 3/4″ instead!

    commcoy–a 50 amp hr battery should be fine.  the only significant draw other than the vent fan is my computer, for watching baseball games.  it has a 65 watt charger, but probably doesn’t draw nearly that much except when charging the battery or spinning the DVD.

    where have you seen one for $350?

    #1229

    faithie999
    Participant

    friz–when i got home yesterday i was able to better assess what happened. When the shell was upside down, we needed to apply thickened epoxy to the outboard edges of the galley flat (where it mates with the “legs” of the bulkhead) and the bottom edge of the galley flat where it mates with the edge of the bulkhead.  then we needed to weight down the assembly while the joint cured.

    either i didn’t properly weight the joint, or too much epoxy squeezed out, because the failure was of the epoxy, not the delamination of the galley flat plywood (except one area of a couple of inches length, where the epoxy joint held but after the rest of the joint failed that couple of inches of solid joint gave way).  just about the entire length of the span between the legs gave way.  also the fillet on the galley side cleanly broke away from the galley flat.

    my initial inclination was to re-glue the joint, then use a 1×1 hardwood stiffener the length of the opening screwed through the galley flat and into the bulkhead.  i realize the bulkhead is only 3/8″, and i’d need to get the screws in the center of the plywood and perfectly plumb so they don’t protrude out of one or the other side of the bulkhead.

    dillon at CLC recommends re-gluing the joint (i’ll also reglue the fillet that broke loose), then as you said you were planning on doing, apply fiberglass tape to the cabin side of the joint.  while i still like the idea of lots of screws, i’ll do what he recommends.  i thought i should also put a strip of fiberglass tape on the galley side of the joint.

    in addition, i’ll fashion some kind of floor in the galley module which will help distribute the battery weight, plus i need to install a hold-down which i hadn’t thought about.

    any thoughts/recommendations?

    thanks

    ps–i know you have a northern tool trailer.  i bought the same one.  i just got back from a 600-mile round trip to see the eclipse.  the aluminum piece that holds the tail lights into the “boxes” stress cracked on both sides of one taillight, and it fell out.  it cracked on one side of the other tail light.  just a heads-up for you.  i bought 2 6×6 1-wide 1/4 inch thick corner braces at the hardware store and will replace the pretty diamond plate aluminum boxes.

    • This reply was modified 2 years, 1 month ago by  faithie999.
    • This reply was modified 2 years, 1 month ago by  faithie999.
    #1237

    ArtisticAdam
    Participant

    Faithie the shear strength of my proposed solution will easily hold the 60 lb. battery. If you have a piece of some regular scrap 3/8″ plywood about the size of the unsupported section of the bulkhead laying around you could test it first.

    Also, since you mentioned your battery was not secured to the galley floor, it is likely that the bouncing of the trailer during travels caused the battery to hop, turning a static load of 60 lbs into a dynamic load hammering on the galley floor.

    If you decide to make a floor inside the galley module for the battery may i suggest going with your initial idea of a “1×1 stiffener” on the under side of the module floor screwed & glued into the galley module sides. Don’t forget to take pictures if you can, hopefully we can help prevent this from happening to more people in the future.

    #1238

    comccoy
    Participant

    This popped up a month or so ago with free shipping and I should have grabbed it then:

    https://www.amazon.com/Lithium-Battery-Electric-trolling-charger/dp/B01MR34NPR

    It is $85 shipping now. I am keeping an eye on it to see if the price drops or the shipping drops again.

    #1239

    friz
    Participant

    I still think the floor is too weak for a 60 lb battery. I think we will see this again. My joints all held. All of my damage came from plywood pulling apart. Granted mine had a couple thousand miles of rough road on it before I had the failure. Nobody puts MTB and gravel races at the end of smooth roads. Just for reference, I have removed all but one of the leaves on the springs and mounted my lights directly to the rear cross member. At this point I’m on my second set of tires (radials this time) and I’m heading out for another race this weekend. I love this trailer, it steals the show everywhere I go. The one thing I would improve is the galley floor. The rest is rolling AWESOME. As far as needing a battery that big. a 100ah battery is only a real world 50ah because to have good battery life you never want to draw more then 50%. Take into account some loss of efficiency over time and the value is even less.

    #1240

    comccoy
    Participant

    I also find this interesting. It would need a box and some voltage regulation etc, but for the price it would still be a lot cheaper than most I have seen:

     

    http://www.ebay.com/itm/LiFePO4-12V-60AH-Battery-10A-Charger-BMS-Rechargeable-Solar-Energy-Power-BY-UPS/182719009313

    #1243

    comccoy
    Participant

    I have also run across this in my battery research and I might feel brave enough to try and build my own battery as I can skip the soldering minus the major wires to get power in and out of the battery.

    Home

    I really like that you can find and replace individual cells as so often with larger batteries just one cell goes bad but the whole thing “breaks”. Here you could even be on the road and a few minutes with a volt meter you could find and then easily replace the one bad cell. The Lifepo4 batteries put out 3.2v each so 4 parallel packs of whatever size will put out ~12.8v. I just need to calculate the AH per X batteries and then look at battery box options once it was all shrink wrapped up. If you buy the cells in batches they get a lot cheaper and I have read a few people have had luck with $1-$2 per cell on ebay, though going through there has been iffy for me several times with poor knock offs etc.

    https://www.aliexpress.com/item/40pcs-Lot-PKCELL-18650-Battery-LiFePO4-18650-3-2V-1200mAh-lifepo4-IFR-18650-Rechargeable-Battery-Batteries/32756553248.html

    Sorry for all the posts, I can’t figure out if/how I can edit my reply from earlier to just add more info.

    #1244

    friz
    Participant

    No need to apologize. Go forward into the unknown and develop awesome tech for the rest of us to benefit from. If I had the time, I would be working on an arduino based TDCM (TearDrop Control Module) to control my lights and fan with the ability control these using bluetooth from my cell phone. It would also be nice to see state of charge on the phone also. I ran out of time this season. I chose to camp rather then tinker. Maybe if I check everything off the list this winter I will return to it.

    #1246

    ArtisticAdam
    Participant

    Friz, I like that accronym TDCM i’ve been piecing together a “home automation” system for the TD using a pcduino (arduino type control board) and OpenHAB automation software. The system will include media center capability and complete electrical system controls via a touch screen monitor.

    I’d also like to include WiFi with this system and monitor trailer backup and side cameras from my phone while driving. The down side with all these nifty gadgets is the need for more and more battery power. If only I could find a good LiFePo4 Battery option with 100Ah that wont break the bank

    Friz, Please let us know when you start working on your TDCM again, maybe we can collaborate.

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