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Date Posted |
Forum
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RE: Mexwanderer
Some nefarious individuals hacked email, tried to hack my bank info, and screwed up my paypal, amazon and ebay accounts. So I've had no gmail since October 28
I've tried to get a temporary email but I'm always asked to provide an email address for confirmation. I must have ten thousand emails unopened.
That’s too bad, you are a valuable asset with your knowledge. I couldn’t have gotten my battery system on my work truck installed as well without your help. Thanks for your contributions to this site.
https://i.imgur.com/kFQOQxIl.jpg
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S Davis
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05/14/23 12:22pm |
Around the Campfire
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RE: Changing from lead acid to LiFePo4 battery?
Just don’t plug in and float your LifeP04 batteries.
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S Davis
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05/02/23 11:54am |
Tech Issues
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RE: Back in the dark ages !
I've read that charging lithiums with an ordinary alternator can smoke your alternator. Investigate before doing that.0
There are many myths designed to scare you into not improving your life.
Alternators come in two flavors.. both are current limited and the myth is since Iithiums can take a rapid charge they will draw more than the alternator can deliver and burn it out... Nope. alternator knows what it can deliver and won't exceed that amount.
Li's however do take a slightly higher voltage.. Oh that could pop a diode.. Again nope.. it won't.
It might not exceed its max amperage but they can over heat and burn up trying to put out max amperage at idle, unless they have temperature protection. I charge a pair of 280ah LifeP04 batteries and they will take all the amperage I can throw at them until about 95% SOC when they start tapering off the amperage.
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S Davis
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02/21/23 10:35am |
Tech Issues
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RE: 9’6” camper so I need an extension ??
Another issue is the pivot point under the overhang, make sure the trailer doesn’t contact the camper going through a dip.
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S Davis
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02/13/23 10:44am |
Truck Campers
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RE: Propane smell inside oven
Get some soap bubbles and check your pilot tube, the nut at the pilot and at the gas valve. I have found lots of small leaks on pilot tubes over the years.
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S Davis
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02/09/23 12:02pm |
Tech Issues
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RE: Wiring 4 awg charging wire to upgrade 8 awg factory wire.
I removed the rear seat in my crew cab and made the enclosure. So have room for the two 280ah batteries inverter and associated wiring.
https://i.imgur.com/SRPapNvl.jpg
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S Davis
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02/05/23 01:46pm |
Truck Campers
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RE: Wiring 4 awg charging wire to upgrade 8 awg factory wire.
My Redarc 50amp just senses the voltage increase from the alternator and turns on, no trigger wire.Nice to have that capability built-in. I don't understand why all dc to dc charger manufacturers don't include the equivalent of a Battery Isolator (BI) or Automatic Charging Relay (ACR) with their units. It's a basic requirement for operating a dc to dc charger in the vast majority of installations.
The 50a Redarc dc to dc charger is a nice unit, built like a tank. See a number of off-roaders using them.
One big caveat though, they cost $500+. One could potentially purchase & stack 4, 40a Renogy dc to dc chargers for 160a of output for $519. Of course, this would require a dedicated, high capacity alternator to provide the necessary current. I've been told Renogy doesn't recommend stacking (connecting in parallel), but I've stacked 2 of them with no issues.
I know but having the charger just work without babysitting it is priceless, especially for LifeP04 batteries. Next step is a dedicated alternater.
https://i.imgur.com/h0bljnhl.jpg
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S Davis
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02/05/23 11:38am |
Truck Campers
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RE: Wiring 4 awg charging wire to upgrade 8 awg factory wire.
My Redarc 50amp just senses the voltage increase from the alternator and turns on, no trigger wire.
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S Davis
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02/04/23 09:21pm |
Truck Campers
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RE: 8 Gauge Wire
Input current will vary depending on wire size and length feeding the charger, that is probably why they don’t list it. I run a 50 amp Redarc and it outputs 50amps with an input of about 53-54 amps, but I have a 1/0 DLO charge line.
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S Davis
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01/22/23 10:59am |
Truck Campers
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RE: Voltage Drop - NOT Park Problem
I'm done here. Thanks for all the reasonable suggestions. If I ever resolve it I'll come back and update this post.
So was the most of the voltage drop at one spot or small drops at multiple spots? Did you check each connection with your meter, it’s not magic it has to be coming from somewhere. Have you checked the start capacitor on the A/C to make sure it’s not the issue/ what are the rated starting amps and what are they actually. Is the voltage drop at the breaker panel the same or close to what it is at the A/C unit?
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S Davis
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01/08/23 01:02pm |
Tech Issues
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RE: In bed fuel transfer tank question
I have a 52 gallon aluminum, it does form condensation(western WA) so I would plan either don’t draw off the bottom and have a drain or have some kind of water separator. I went off the bottom into a water separator and then to a 30gph pump which is plumbed into the trucks filler neck. I have the pump hooked up to a mechanical 30 minute timer, one twist and about 15 gallons transfers.
https://i.imgur.com/tNFNfH2l.jpg
https://i.imgur.com/dWzIJpKl.jpg
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S Davis
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01/08/23 11:34am |
Tow Vehicles
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RE: Filtering Our Diesel Storage Tanks For on Road Use
A lot of nice places to see, here is Mount Baker from the south.
https://i.imgur.com/MLGlA9yl.jpg
https://i.imgur.com/76M3Gkkl.jpg
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S Davis
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01/04/23 12:48pm |
Tow Vehicles
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RE: Filtering Our Diesel Storage Tanks For on Road Use
If your tank is Metal I would be worried about the extra moisture, I have a 52 gallon aluminum and it forms condensation. I went with a dedicated moisture filter, and will get water out the drain.
https://i.imgur.com/Ss7uSLbl.jpg
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S Davis
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12/30/22 06:19pm |
Tow Vehicles
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RE: Lithium battery box temps
This is my heating for my two 280ah LifeP04 batteries. I use a 25 watt silicone heat pad sandwiched between aluminum plate and blow air across it, kept them at 50f at 8f outdoor. They are installed in the rear seat area of my crew cab.
https://i.imgur.com/vR3FsDQl.jpg
https://i.imgur.com/x6BSdKel.jpg
https://i.imgur.com/uTotJ1Yl.jpg
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S Davis
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12/30/22 10:38am |
Truck Campers
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RE: DIY Li Battery Heater...A REAL TEST!
DIY Battery Heaters...A REAL TEST!...got down to 7F degrees last night. At 7am the battery compartment is at 35 degrees. Controller is set to turn on at 35F and off at 38F........The batteries are at 90% on the monitor.....Working GREAT!... http://rvbprecision.com/rv-projects/lithium-battery-heating-project.html
http://rvbprecision.com/rv-projects/lithium-battery-heating-project.html
It doesn’t take much to keep them warm, I set mine at 50f with 25 watt silicon heat pads. We got down to 8 degrees this week and no problem keeping my two 280 ah LifeP04 batteries warm. It’s nice hoping into the truck at 8 degrees and having a heated throw on your seat.
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S Davis
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12/24/22 11:59am |
Tech Issues
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RE: Lithium for dummies: need advice in simple terms
. . . What I don't know is if below freezing will affect the battery life while discharging or storing.Specs vary from manufacturer to manufacturer, but generally speaking, maximum recommended discharge current tapers downward as temps drop below 32f or so. Probably wouldn't want to do more than a .10c - .15c discharge at temps below, say, -10c (14f).
Long-term storage recommendations are not too stringent. If you follow the temp recommendations for charging (typically 0-40c; 32-104f) that should be acceptable. If you want the absolute best for your cells, strive for 25c (77f) and 30-50% SOC.the specs for the new cells I ordered are pretty good that way, 0.5C discharge down to -30C short term storage of a month -40C/F long term storage -25C and charger from -5C to +60C. but it totaly does depend on the manufacture and for premades, they tend to add a little more of a buffer so they have less warenty clames they have to pay.Very impressive. As far as advertised specs, it can work both ways. Make them conservative so they can reduce warranty claims, or make it look like their cells walk on water to sell more cells/batteries. Me, I tend to give the research and testing produced by independent labs the most creedence.
these are the new K cells from EVE and the specs are from eve's testing sheets not a salesman ;) . now am I going to set them to charge ar -5C, naa I'll keep it at +1 as my batteries are inside the living space so will never get that cold anyways, I may test the cold discharge though... well then again naa, I aint going camping at -30C haha, but the thing of interest to me was you can short term store much colder than long term (short term they describe as 30 days or less) and the fact that they seam to be a significantly more robust than the normal 280AH cells rated at 5000 cycles (100% to 0%) instead of 3500and I realy like the new double tapped termanals on them two bolts for power path instead of one skinny post.
Steve
They are not much more robust, they changed the testing specifications. The older LF280N that I have are rated at double the amp draw, 1c for 3500 cycles with a compression fixture. The new LF280K are rated at half that at .5c for 6000 cycles with a compression fixture.
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S Davis
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12/13/22 11:24am |
Tech Issues
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RE: Lithium for dummies: need advice in simple terms
Mordecai, what do you use to monitor whether you are short amps? (Different from a short circus, I think.). ;)
No, seriously, which device will give you an accurate picture of the remaining battery capacity? Using a cheap multimeter, I often check the voltage on my lead acid batteries, on the theory that any reading below 12.1 means that I've got a state of charge less than 50%.
But with lithium batteries, the voltage does not drop, I think. The battery goes from "full" to "dead," if I remember correctly.
Full charge is about 13.4 volts, at 12 volts you are at about 10% charge with LifeP04. Voltage does drop with state of charge just not as much as lead acid.
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S Davis
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12/08/22 07:11pm |
Tech Issues
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RE: Lithium for dummies: need advice in simple terms
It really doesn’t take a lot to keep the cells warm, I use a 3”x3” 12 volt 25 watt silicon heat pad on each battery and they have worked perfectly down to 8f in back seat area of my crew cab. I have them set about 50 degrees, with two 280ah batteries I can spare the ah to run them.
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S Davis
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12/08/22 11:07am |
Tech Issues
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RE: Lithium for dummies: need advice in simple terms
S Davis.
Some take away's about LiFePo4 batteries
"There is more to calendar life and how quickly a LiFePO4 battery will age: State-Of-Charge has something to do with it as well. While high temperatures are bad, these batteries really, really do not like to sit at 0% SOC and very high temperatures! Also bad, though not quite as bad as 0% SOC, is for them to sit at 100% SOC and high temperatures. Very low temperatures have less of an effect. As we discussed, you cannot (and the BMS will not let you) charge LFP batteries below freezing. As it turns out, discharging them below freezing, while possible, does have an accelerated effect on aging as well. Nowhere near as bad as letting your battery sit at a high temperature, but if you are going to subject your battery to freezing temperatures it is better to do so while it is neither charging nor discharging, and with some gas in the tank (though not a full tank). In a more general sense, it is better to put away these batteries at around 50% – 60% SOC if they need longer-term storage.
Melted battery
If you really want to know, what happens when a lithium-ion battery gets charged below freezing is that metallic lithium is deposited on the negative (carbon) electrode. Not in a nice way either, it grows in sharp, needle-like structures, that eventually puncture the membrane and short out the battery (leading to a spectacular Rapid Unscheduled Disassembly Event as NASA calls it, involving smoke, extreme heat, and quite possibly flames as well). Lucky for us, this is something the BMS prevents from happening."
So if you have solar--turn it off during storage. I don't like that.
This is the summary from the article:
"To sum up, for long and happy LFP battery life, in order of importance, you should be mindful of the following:
Keep the battery temperature under 45 C (113 f) (under 30C if possible (86 f)) – This is by far the most important!
Keep charge and discharge currents under 0.5C (0.2C preferred)
Keep battery temperature above 0 C (32 f) when discharging if possible – This, and everything below, is nowhere near as important as the first two
Do not cycle below 10% – 15% SOC unless you really need to
Do not float the battery at 100% SOC if possible
Do not charge to 100% SOC if you do not need it"
The above are from https://www.solacity.com/how-to-keep-lifepo4-lithium-ion-batteries-happy/
another good page on care and feeding:
https://dakotalithium.com/2021/09/22/how-to-charge-dakota-lithium-and-lifepo4-batteries/
Ok so you are getting it from a company trying to sell batteries instead of the manufacturer of the batteries, their recommendation has more to do with warranty than affecting cycle life.
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S Davis
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12/07/22 08:45pm |
Tech Issues
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RE: Lithium for dummies: need advice in simple terms
S Davis,
I got the figures from the wobbly wide web. If I were going Li I'd go 40% to 85%. I never will due to cold.
Your document is too blurry for me to read.
Ok well I have read just about every spec sheet for the currently available LifeP04 cells and have never seen that in any of them, all their definitions of a battery cycle are from full charge to 2.5 volt cutoff at the stated amount of cycles.
Do you have any spec sheets that say that? If not you are giving out false info. You can use 100% of the stated capacity and still get the rated cycles according to the manufacturers of the cells.
I will try and get a better screen shot, this might be a little better.
https://i.imgur.com/tPVpRbql.png
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S Davis
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12/07/22 02:44pm |
Tech Issues
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