User Tag List

Thanks Thanks:  0
Page 1 of 2 12 LastLast
Results 1 to 10 of 14

Thread: Does TV charge lithium?

  1. #1
    Site Sponsor AZMike's Avatar
    Join Date
    Oct 2020
    Location
    Southern Arizona
    Posts
    244
    Mentioned
    2 Post(s)
    Tagged
    0 Thread(s)

    Does TV charge lithium?

    Maybe I missed it, but I have not found a post on the subject. Will a tow vehicle with just a lead acid battery charge a trailer with a lithium battery while towing? My truck does have the tow package with the high output alternator, but it is my understanding that the "high output" is just the current, not higher voltage.
    Mike & Karen
    2021 Imagine 2600RB
    2011 Toyota Tundra 5.7 RW, Tow Package
    Husky Centerline WDH
    iGen4500DF, Prodigy P2
    Happily Retired!

  2. #2
    Site Team Ynot4me2's Avatar
    Join Date
    Mar 2020
    Location
    ON & QC Canada
    Posts
    1,725
    Mentioned
    10 Post(s)
    Tagged
    0 Thread(s)
    I am by far no expert and I'm still learning. In fact I'm as green as they come on this subject. Hopefully the more experience will chime in soon and correct me. Yes your TV will charge but not effectively. Best to get a DC to DC charger for the TV an tt hook up.
    Steph & Lise
    2019 F150 Lariat 2.7 EB
    2020 Imagine XLS 22MLE

  3. #3
    Seasoned Camper
    Join Date
    Feb 2019
    Location
    Wherever we park it
    Posts
    404
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)
    The short answer is yes. The long answer is whether lead acid, AGM or lithium batteries the charge to the batteries is minimal because the distance from the alternator with minimal wire size means there is significant voltage drop. So know your batteries will receive a charge while driving but I would not depend on it to provide a full and complete charge.
    Regards, Bruce, Lin An, Kenji & Suki (Our two Akitas)
    2019 Solitude 310GK-R
    2015 Ram 3500 Big Horn CC, TD, Aisin Tranny, DRW

  4. #4
    Site Sponsor bertschb's Avatar
    Join Date
    Jan 2015
    Location
    Bend, OR and Palm Springs, CA
    Posts
    2,915
    Mentioned
    22 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by AZMike View Post
    ... Will a tow vehicle with just a lead acid battery charge a trailer with a lithium battery while towing?
    My understanding is most trucks will put out 7-9amps to the RV batteries and it doesn't matter if the RV has lead acid or Lithium.
    Brian & Kellie
    2020 Solitude 310GK-R, FBP, 1,460w solar, 540ah BBGC3, MORryde IS w/disc brakes
    2020 F-350 Platinum SRW Powerstroke Tremor, 60g TF fuel tank, Hensley BD3-F air bag hitch

    Previous setups:
    2019 Solitude 373FB-R, 2019 F-350 Platinum DRW Powerstroke, Hensley BD5 air bag hitch
    2016 Reflection 318RST, 2016 GMC 3500 Denali SRW Duramax, Hensley BD3 air bag hitch

  5. #5
    Site Sponsor AZMike's Avatar
    Join Date
    Oct 2020
    Location
    Southern Arizona
    Posts
    244
    Mentioned
    2 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by bertschb View Post
    My understanding is most trucks will put out 7-9amps to the RV batteries and it doesn't matter if the RV has lead acid or Lithium.
    True, but my main concern is that lithium requires a slightly higher voltage to fully charge, and if we are boondocking many nights is a row will my TV be up to the task of keeping the battery "topped off".
    Mike & Karen
    2021 Imagine 2600RB
    2011 Toyota Tundra 5.7 RW, Tow Package
    Husky Centerline WDH
    iGen4500DF, Prodigy P2
    Happily Retired!

  6. #6
    Left The Driveway
    Join Date
    Jun 2020
    Posts
    11
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Here is a chart on wire sizes and current.
    Automotive Wire Amperage Capacity Chart

    Recommended Length and Amperage for Automotive Wire while maintaining a 2% or less voltage drop at 12 volts
    Automotive Wire Size 5 Amps 20 Amps
    16 Gauge Wire (AWG) 11.5 ft 2.9 ft
    14 Gauge Wire (AWG) 18.4 ft 4.6 ft
    12 Gauge Wire (AWG) 29.4 ft 7.4 ft
    There other problem will be your TV charging system. It only monitors your TV battery, so it will decrease as that battery is charged. It could care less what's at the trailer end. Your best bet would be a DC to DC charger like Ynot4me2 stated above.
    2020 Chevy Crew Cab RST
    2020 Transend 30RBS

  7. #7
    New Member
    Join Date
    Apr 2021
    Posts
    3
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    The standard 7 pin connector does not have sufficient amperage to charge lithium batteries. Lithium batteries can take a lot of amps for charging. The best way to charge them with a tow vehicle is with a DC-DC charger as mentioned. That is wired with a bulky wire from your alternator to the DC-DC charger to you batteries. They range in capacities but usually 30-50 amps. A 50 amp DC-DC charger would charge a 200 amp hour lithium battery array from dead to full in 4 hours of driving. The details of wiring it are beyond me - I will have a pro do it.

  8. #8
    Left The Driveway Luke611's Avatar
    Join Date
    Apr 2021
    Location
    Moundridge, Ks
    Posts
    10
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    So my hopes of the TV fully recharging the trailer batteries are in vain? I guess solar panels will be on the horizon for us.

    Sent from my SM-N975U using Tapatalk
    1992 Ford F-150 ext cab
    2021 Grand Design Momentum 31g

  9. #9
    Seasoned Camper
    Join Date
    Oct 2018
    Location
    Eastern Washington
    Posts
    122
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Yes, but in my experience it maxes out at 50-70% state of charge because the lithiums take a higher voltage to charge (14.4ish and the alternator is probably around 13.8). I disconnected our TV charging since we have solar now that charges just as much while driving. There are very nice DC to DC converters to fix just this problem, and you can limit the charge rate with them too.

  10. #10
    Fireside Member
    Join Date
    Oct 2020
    Location
    Hudson Valley, NY
    Posts
    45
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    @AZMike - what size battery are we talking about?

    I have a large alternator, I get 14.5V at the battery, and I only get 13.1V / 7A at the trailer battery from the 7-pin.
    That is below the 13.2 nominal Lithium battery voltage, so it might maintain the current low SOC, I doubt I'm charging much.

    Even if you could get 14+V back there, a 100Ah battery at 50% state of charge will take over 7 hours to charge at that rate.
    Do you really want to idle your truck that long?

    The only realistic options for boondock charging are:
    1 - Solar
    2 - Small generator with specific 60-80A Lithium charger. Couple of hours and done for a few more days.

    If you don't want to run the generator that long... do it an hour a day.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

DISCLAIMER:This website is not affiliated with or endorsed by Grand Design RV, LLC or any of its affiliates. This is an independent site.