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offgrid
Senior Member
Joined: 23 Jul 2018
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Posts: 5290
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Topic: The tongue of the Rpod Posted: 22 Sep 2018 at 7:29am |
Oh, one other thought, the Li batteries do not outgas so they really don't need to be on the tongue. Besides, as expensive as they are you might not want them out there. And they don't like to operate below freezing so keeping them in the heated space would be good as well. You could mount them in one of the many unused spaces under the bed or settee. That would help with the tongue weight and space. That is my plan when I convert over the Lithium this winter on my trailer.
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1994 Chinook Concourse
1995 RV6A Experimental Aircraft
2015 Rpod 179 - sold
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GlueGuy
Senior Member
Joined: 15 May 2017
Location: N. California
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Posts: 2624
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Posted: 22 Sep 2018 at 10:01am |
Would the WFCO or PD converter be able to charge the LI batteries properly? Or would you also need to replace that to accommodate?
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bp
2017 R-Pod 179 Hood River
2015 Ford F150 SuperCrew 4WD 3.5L Ecoboost
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offgrid
Senior Member
Joined: 23 Jul 2018
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Posts: 5290
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Posted: 22 Sep 2018 at 11:37am |
Good question. You definitely need to change the charging algorithm. Li ion batteries cannot be allowed to overcharge, in fact its better never to fully charge them or do so only rarely, while of course lead acid batteries need some overcharging frequently. OTOH Li batts don't need a complex multistage charge process, just a bulk charge to a preset max voltage. Lithium batteries instead need a battery management system (BMS) to balance the charge on each group of series cells. I believe the Battleborn battery comes with that built in so you don't have to worry about it.
anmam did a great post on this forum earlier this year on his conversion. I believe he bought a Li Ion charger board from Progressive Dynamics and used it to modify his WFCO. He also used the Battleborn battery IIRC.
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1994 Chinook Concourse
1995 RV6A Experimental Aircraft
2015 Rpod 179 - sold
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marwayne
Senior Member
Joined: 25 Oct 2011
Location: Edmonton AB Can
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Posts: 1002
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Posted: 22 Sep 2018 at 3:12pm |
I'm running about 3600#. The thing I don't understand is this. I have a 2011 172 dry weight 2113# load capacity 1066# total weight = 3179# The 179 - 2017 -- 2018 dry weight 2756# load capacity 1036# = total weight 3792#, and both trailers have the same axle rated at 3500#.
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If you want something done right, do it yourself.
2011 RP172, 2016 Tundra 5.7 Litre, Ltd.
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Bradywan
Newbie
Joined: 13 Sep 2018
Location: Lebanon Oregon
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Posts: 6
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Posted: 22 Sep 2018 at 3:15pm |
Marwayne, Truly impressive mods. Some of the best I’ve ever seen.
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lostagain
Senior Member
Joined: 06 Sep 2016
Location: Quaker Hill, CT
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Posts: 2583
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Posted: 22 Sep 2018 at 3:36pm |
Maybe they put helium in the tires of the 179's??
In all seriousness, the GVW difference doesn't appear to make any sense. Looks like there is no margin of safety in the capacity of the 179; indeed its axle capacity is exceeded. Makes me glad I have a feather light 172, with more things removed than added. At least there is a pretty good margin of safety with the stock axle.
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Never leave footprints behind.
Fred & Maria Kearney
Sonoma 167RB
Our Pod 172
2019 Ford F-150 4x4 2.7 EcoBoost
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offgrid
Senior Member
Joined: 23 Jul 2018
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Posts: 5290
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Posted: 22 Sep 2018 at 3:52pm |
Yes absolutely the axle load on the heavier pods is an issue.
My 179 weighs in at about 3900 lbs loaded. But 570 lbs is on the tongue not the axle, so that gives 3330 on the axle. But then when I put about 600 lbs tension on the 30 inch bars of the wd hitch to reduce the TV rear axle loading I generate 1500 ft lbs of moment which is balanced by about 120 lbs additional load being transferred to the trailer axle. So now I'm at 3450 on the axle. So not exceeded but dang close, and that's not counting the weight imbalance between the driver and passenger sides.
And that's why I want to invest in a heavier axle....
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1994 Chinook Concourse
1995 RV6A Experimental Aircraft
2015 Rpod 179 - sold
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mcarter
podders Helping podders - pHp
Joined: 07 Apr 2016
Location: Greenbrier, TN
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Posts: 3419
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Posted: 22 Sep 2018 at 4:44pm |
Hmmm, I wonder how many axle failures have a WDH involved, curious and not being problematic?
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Mike Carter
2015 178
" I had the right to remain silent, I just didn't have the ability."
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offgrid
Senior Member
Joined: 23 Jul 2018
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Posts: 5290
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Posted: 22 Sep 2018 at 6:26pm |
I wonder the same thing...
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1994 Chinook Concourse
1995 RV6A Experimental Aircraft
2015 Rpod 179 - sold
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offgrid
Senior Member
Joined: 23 Jul 2018
Online Status: Offline
Posts: 5290
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Posted: 23 Sep 2018 at 1:06pm |
GlueGuy, back to your question yesterday on Li Ion charging, I took a look at the Battleborn website today and they say that as long as your existing charger doesn't exceed 14.4 volts it can be used with their batteries as is, so our WFCO's should in theory not cause a problem. They do imply that that might not be the most efficient charge protocol for their product though and have some other recommendations. WFCO, PD and pretty much all the other charger manufacturers have specific Li Ion chargers or specific programmable Li Ion settings now so I guess it would be good to sift through all that before making a decision what to use.
In my case, my current thought is to move to 24V when I go to Li Ion to reduce copper costs and weight and voltage losses running the big loads (the air conditioner mostly) so I'd need a different charger anyhow. I'll probably go with one of the 3kw bidirectional inverter/chargers.
For the OP, the battery management system in the Battleborn battery apparently won't allow charging at batt temps below 25F. I think probably all Li Ion batteries are going to be like that. So if you know you'll never use the pod in those kind of conditions you can leave them on the tongue as you were thinking, otherwise it would probably be better to keep them in the heated space somewhere. Or go with lead acid batteries as others on this thread have suggested.
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1994 Chinook Concourse
1995 RV6A Experimental Aircraft
2015 Rpod 179 - sold
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