Going Lithium

[richminaya]

Any suggestions? Want to put my 200Am (AmpereTime) Lith Batt on the tongue. Think I can find a suitable enclosure and construct one.

My concern is: what do use for a temperature cut off? Any ideas? How to make sure the controller doesn't send DC current to the battery, say when it goes below 35F. I have both the GoPower GP-PWM that came with the unit, but no indication of any sensor or cut off.

Also have a NewPowa MPPT that has a temperature sensor for the battery - however I think that is if it goes too high. I am concerned about making sure not current is leaked to try to charge when cold as I have read the permanent damage which will prevent decent charging later.

This would have to be a temp monitor at the batt, I believe.

The other option is burning watts to wrap with some kind of heating pad.

I just got the unit and want to take it someplace warm to run it through it's paces. Def over Lead batteries.

Thanks.

Rich
St. Johns, MI
EPro FBS19, 2 X 190 GoPowa panels on roof, addl 200W to set up external solar and plug in the side (which just goes to the batt anyway) .... addl 300w foldable Dokia solar system to move (light!!) around while boondocking or charging miscellaneous ..... have 3 lead batts (all same brand) for total 340 (170!!!Ah) reserve (but can't be on same bus)... figure out wiring next year after the warranty period expires.

[W5CRE]

The only solution I see is to manually disconnect the solar charger when the temperatures go low. Maybe you can install a secondary battery shutoff switch just for the solar controller. Make sure it can handle the amps. Then I recommend the 0°C,0°F method. If the temperature is below 0°C stop charging and if the temperature is below 0°F stop using. The AmpereTime battery does have a very low price for a reason.
Personally somewhere between 0°C and 0°F I pack up and go home.

[TitanMike]

Doesn't your Ampere Time battery have a BMS with Lo Temp cutoff?

Hard to imagine a battery without at least this feature as it's so important.

If so, you really don't need to do anything extra except maybe just a Switch/Circuit breaker on the PV input to he solar controller just to be sure.

Another optption would be to install a tank heater pad like the self regulating FACON units sold on Amazon. Fairly reasonable in price and pads are available in several configurations you could wrap around battery. Pads like these usually start heating when temp drops less than upper 30's (F) and shut off around 60(F). Find or construct a battery box larger than battery and surround battery with some fiberglass board type insulation with foil face. Some on bottom and all sides, with heating pads on battery sides.

I opted to install my LiFePo4 batteries inside where I didn't have to worry about freezing temps and heating. When stored my batteries are shut off and they can go for months without loosing any significant amount of charge.

Remember, once installed LiFePo4 batteries require no more physical access than one would need with their Cell Phone Battery. They can be hidden just about anywhere.

[richminaya]

Will Prowse on YouTube did 2 teardowns/reviews of this particular battery. I think Jan 21 and a second in the spring. The first was not so positive. The 2nd was better. Will proved that some of these cheaper LiPO4 batts like this one - - - DO NOT have the low temp cutoff, unfortunately.

The tank heater pad may be the best answer. This is like 2 steps forward (Lithium, 100 more Ah, actually more, solar ...) and now I gotta suck off it just to keep the batt alive. lol. Since it is under warranty, I'm nervous of doing certain modifications. As I get better info from folks here, I may steel myself to make changes.

I def appreciate the suggestion on the heating pads. Will check out. As to getting the right size box, so far that is def a more specialized situation I found one possible company, but I think they only sold commercially and not retail.

Inside! That is the long term plan, which will require some heavier rewiring, cutting holes, etc and I figured eventually I could get another and have 400 Am in LiPO4 stored right under the front of the couch/fold-out bed. Exactly enough space (9 inches) there that are unused.

W5CRE - is that a general rule that you can draw only above 0F from a Lith Batt? I seriously do not see that ever being a problem other than if I'm transitioning to or away from home.

[richminaya]

.... I forgot to ask about this serious concern.

If one tries to charge a Lith Batt below 32F, you can permanently ruin the ability for a full recharge ....

If this is the case, would I have to be concerned even about the trickle charge coming from my truck?

That's why I was thinking/hoping there was some sort of cut-off or thermocouple that could be right at the Batt, I assume, on the positive (not negative?) input

I really appreciate the help!

[TitanMike]

Originally Posted by richminaya

Will Prowse on YouTube did 2 teardowns/reviews of this particular battery. I think Jan 21 and a second in the spring. The first was not so positive. The 2nd was better. Will proved that some of these cheaper LiPO4 batts like this one - - - DO NOT have the low temp cutoff, unfortunately.

The tank heater pad may be the best answer. This is like 2 steps forward (Lithium, 100 more Ah, actually more, solar ...) and now I gotta suck off it just to keep the batt alive. lol. Since it is under warranty, I'm nervous of doing certain modifications. As I get better info from folks here, I may steel myself to make changes.

I def appreciate the suggestion on the heating pads. Will check out. As to getting the right size box, so far that is def a more specialized situation I found one possible company, but I think they only sold commercially and not retail.

Inside! That is the long term plan, which will require some heavier rewiring, cutting holes, etc and I figured eventually I could get another and have 400 Am in LiPO4 stored right under the front of the couch/fold-out bed. Exactly enough space (9 inches) there that are unused.

W5CRE - is that a general rule that you can draw only above 0F from a Lith Batt? I seriously do not see that ever being a problem other than if I'm transitioning to or away from home.

You only need to heat when the battery temps are lower than 0 (C) or 32 (F).

as for battery boxes check out companies that sell Battery boxes to the Marine industry (not just recreational boaters). They cost a little more but are usually far more substantial than the plastic ones sold for small boats.

Locally we have a company "Fisheries Supply" that has been outfitting large fishing boats for almost forever.

Here's a link to some battery boxes I'd consider for the Ampere Time battery.

https://www.fisheriessupply.com/mari...50%20113417143

A box for a Group 8D battery would have room for the Ampere Time battery and leave some room for insulation around it.

[DogFather]

Although richminaya already has a battery, the following advice is too late, but might benefit others considering a LiFePO4 battery.

What harms a Li battery is charging it if it's too cold. Batteries like the one below sense the temperature and turn on a built-in heater to keep it warm enough to charge at ambient -5 deg. F, they say. That avoids the external sensor, heating pads, etc. I got some and have been very happy with performance.
https://www.lifebluebattery.com/rv-b...m-battery.html

[corn18]

Can you move the battery inside? You can discharge below freezing but not charge. My LiFePO4 batteries are in my heated basement. I turn on the furnace and let it run until my Victron temp sensor at the battery says it is warm enough to charge. Then I turn on any charging devices. Although until you mentioned it, I hadn't thought about the charge line coming from the truck. That is not switched. Have to think on that one.

Leaving it on the hitch is going to be problematic, even with heaters.

And if anyone else is reading this, make sure you buy LiFePO4 batteries with a cold temp cutoff.

[TitanMike]

Originally Posted by corn18

And if anyone else is reading this, make sure you buy LiFePO4 batteries with a cold temp cutoff.

It's very possible some battery manufactures are "going cheap" on the BMS, eliminating cold temp sensors, etc, and target marketing warm climate Solar system storage.

Definitely a decision one will need to make. Go with the liw battery price then give back all the savjngs by having to purchase extra equipment.

[richminaya]

TitanMike: It would appear that they are going cheap or cutting corners, but the overall reviews (amazon) are very favorable. I paid half of what was recommended by (below) but didn't think a solution would cost a lot

Dogfather: The battery you mentioned is $1600 compared to the $800 I paid. I gotta believe a few bucks should remedy the problem. Right now, the cheap out of turning on heating pads seems the simplest solution. Until I forget one time and destroy the battery. Just like, the red always goes to the positive and the black always positive. Until one day, you try the losing 50% choice which is inevitable.

Corn18: Right! See my earlier post. Inside is the long term solution for so many reasons - except it's already winter, I don't have an inside warm garage to work in, I should cut the distance from the batts on tongue to the inverter by about 20 feet (once roundtrip), stay warmer inside ......... That will come next year.

[TitanMike]

Went back and watched a couple videos by Will Prowse on the Ampere Time and Chins' batteries. In his opinion they are identical, coming from same factory, using same parts/design. Just different packaging and labels.

He also mentioned that the lack of a low temp sensor could be overcome if charging with Solar and using a Solar Controller with temperature sensor. Victron was mentioned.

As for charging from a tow vehicle if battery below freezing, charging from ANY source will harm the battery. Vehicle charging source would definitely need to be isolated just like from Solar and from Converter.

Charge well when temps are warm and you'll still be able to use until temps drop to ~-4 F or so.

[richminaya]

TitanMike - Always enjoy your posts.

I saw Will Prowses teardowns, as well. That guy is an outstanding source of info just like FRForum.

Even if I got a Victron I would still have to run a wire from the sensor built into the wall and out to the tongue, which falls under the "later" category. The simple cut-off switch at the battery may be the short and simple answer.

Or if I am taking off to the SW or Florida from Michigan, I can always work on the unit while boondocking. Understandably, being that far away from home for a long period is exhilarating enough. The thought of not having "that tool or part" or having something go bad 1500 miles away is not good. Wish winter would have started late.

I'll update as I figure it out. Thanks all.

[TitanMike]

Originally Posted by richminaya

TitanMike - Always enjoy your posts.



I saw Will Prowses teardowns, as well. That guy is an outstanding source of info just like FRForum.



Even if I got a Victron I would still have to run a wire from the sensor built into the wall and out to the tongue, which falls under the "later" category. The simple cut-off switch at the battery may be the short and simple answer.



Or if I am taking off to the SW or Florida from Michigan, I can always work on the unit while boondocking. Understandably, being that far away from home for a long period is exhilarating enough. The thought of not having "that tool or part" or having something go bad 1500 miles away is not good. Wish winter would have started late.



I'll update as I figure it out. Thanks all.

The Victron temp sensor is connected from battery to the shunt. The two wires from the battery terminal mounted sensor provide positive voltage and temperature to the two small wire terminals on the shunt.

If using a smart solar controller the temps and voltages from the shunt are "shared".

Not sure if Victron Converter/Chargers are able to be switched off via temp sensor as well as their DC-DC chargers but you might want to look at their products and see.

Might provide a simple system for your needs.

NOTE: If you use the Victron BMV-712 monitor it has Bluetooth capability. You don't need to wall mount the meter. Just install the shunt and if you don't want to mount the meter just secure it in a dry spot (in ziploc bag) and use your Smartphone for monitoring and setup.

The meter version (not smart shunt) also has a built in relay you can use to controll outside functions like turning on heaters, on/off charging sources, all determined on easily programmed parameters.

Relay is a low current capacity but can be used to handle controll voltage for larger higher current relays.

[richminaya]

I am going to look at that to make sure I did not miss something. Thank you for that reminder. I have looked at a couple things, but unsure about how to handle (ultimately) the amps.

How many thumbs up would I get if I asked: "How many of us wish we were boondocking full-time?" I still work (run my own business) and had pretty good luck spending a lot of the Summer working my the old RV. No difference although some people really do like to meet in person.

Goal is to do this boondocking full time in the new Solar. Just wish I was able to get the unit when weather didn't suck.

[TitanMike]

Originally Posted by richminaya

I am going to look at that to make sure I did not miss something. Thank you for that reminder. I have looked at a couple things, but unsure about how to handle (ultimately) the amps.



How many thumbs up would I get if I asked: "How many of us wish we were boondocking full-time?" I still work (run my own business) and had pretty good luck spending a lot of the Summer working my the old RV. No difference although some people really do like to meet in person.



Goal is to do this boondocking full time in the new Solar. Just wish I was able to get the unit when weather didn't suck.

On "handling the amps"---- if you need to switch high currents using a relay rated for the current in question is always the way to go. Small switches or low capacity relays often built into control devices can then be used to operate the heavy relays.

This is an especially good way to go if one has a switch that is often burning up like used to happen in older cars/trucks were towing trailers with lots of tail and clearance lites.

Also a cure for turn signal fast flash when a variable load flasher was not used. Relays on turn and brake lites have become common. Add trailer and no change in flash rate or burning up flasher.

[richminaya]

Don't use much as Never turn on the a/c ... the microwave would be nice to have connected to a circuit the Inverter feeds, but (typical) that outlet is only hot when connected to shore power or the gen.

When I get a break from work, I'm going to look at the victron website.

One other quick question - if the PWM controller that is installed is rated for 30 amps, I assume that is the fastest I could ever charge back up. Assuming 5 perfect sunny hours, I get back is 150Ah.

[TitanMike]

Originally Posted by richminaya

One other quick question - if the PWM controller that is installed is rated for 30 amps, I assume that is the fastest I could ever charge back up. Assuming 5 perfect sunny hours, I get back is 150Ah.

Just remember that PWM solar controller efficiency is LOW. As low as 80-85%.

That alone will slow recharging.


In order to get 30 amps of charging you'll need over 600 watts of solar panels to overcome the inefficiencies inherent to PWM controllers and usual sub-optimum orientation of panels to sun.

Even with a pair of 100 watt panels wired in series for 200w output at 5.6 amp, feeding an MPPT controller, and carefully aiming panels at sun, the max current I can feed my two Battleborn batteries is ~15 amp.

[richminaya]

Crap. 2 steps forward, 1 step back - again. Thanks for that reminder.

Which means I should probably look at the Newpowa MPPT that I have. I also have a Dokia that is pretty cheap so the former may be better.

They already have a hole cut in the RV wall with the GoPower PWM inset. Aesthetically and in a small living area, I have to think about that some more. Something sticking out 3 inches may not be that attractive ....

Mike, maybe this is overkill, but for Michigan camping, where clouds come in in November and leave by March (!), this is the more detailed stack:

Solar Panels
- 2 X 190W from GoPower from factory
- 1 X 200W from Newpowa either for up on the roof or portable to chase after the sun
- 1 X 300W from Dokia. Saw one in person. Looks cheap, but seems to perform as advertised. Definitely light enough you could carry to the beach

Batts
- 1 X 200Ah Ampere Time
- 2 X 100Ah cheap lead acid
- 1 X 140Ah (bought same time, same company)
+++ I was hoping to keep the lead-acid (170A @ 50%) as reserve in a little closet in the FBS19. Again down the road, due to rewiring hassle
*- 1 X Bluetooth Speaker, W-KING Outdoor Wireless Portable Speaker with 8000mAh Power (lithium). This is a 2 fer; It plays all day at full volume with energy leftover and it can be used to store energy and charge other devices, sort of like a solar generator (?), but for $50 Amazon

Gen
- 1 X 30 year old quiet Honda 1000W portable Generator as last resort for power. This little gennie was one of the best "investments" ever made.
- 1 X Sportsman 3250/4000 that is dependable, but loud and will hopefully now stay in the barn.

This is like every other hobby/interest: a dark, black hole that just keeps sucking money. LOL.

[Roger R]

Rich, a couple of things to consider.

Agree aesthetically something sticking out from the wall 3 inches is not good and MPPT controllers typically have cooling fins so hanging one on a wall, it will stick out. The wires would be exposed also not visually pleasing. However, a lot of MPPTs come with remote displays. The challenge is covering the existing GoPower PWM hole with one. Your Newpowa MPPT has a communication port, but I didn’t see any remote displays available from Newpowa.

I did notice your Newpowa Solar panels have a voltage significantly below the GoPower ones. Hopefully you are planning on running both brands on different charge controllers. In Parallel the voltages want to be the same on any solar panel going to the same controller or the lower solar panel will degrade the output from the higher voltage solar panel. Believe you are not going series. The Newpowa MPPT has a 50V or so voltage input capacity.

I’m evaluating the same considerations you are. My Flagstaff 29RBS has the 190W GoPower panel on the roof, 1Kw inverter, 12V refrigerator, and 200AH FLA batteries with the Victron Smart Shunt. I understand my battery loads and my current capacity is not enough. Looking at converting to LIFEPO batteries. But want to plan out the full system before I buy. I am also in Michigan and will tow in the winter so if I only have the lithium batteries, believe I will need some sort of heater for them even if installed inside. (brakes, refrigerator, and charging from the 7-pin) This forum and Will’s videos are great resources for what we’re trying to do.

[richminaya]

Hey Roger,

Since we are both in Michigan, let's flag each other's contact info. We're both trying to do much of the same with our rigs.

- I think any major change in controllers will wait for on the wall. I simply may have to tolerate the reduced efficiency on the PWM; I've blown the budget for a while

- On the Solar mis-match, I'm am glad you pointed out the voltage question as I will have to check this out a bit more. The idea situation would be I get enough sun from the 380w on the roof, and I could use the Newpowa to move around and keep the 2nd bank recharging. I talked with the rep at Newpowa, and he did not indicate any problem with the different solar panels. However, if I need to, I have the extra controllers.

I think you will absolutely want more watts as you already mentioned. Doing some minor calculations, I felt 400W was a minimum with an additional 200w that's portable to add to the charging. Ultimately 200Ah battery will not be enough for boondocking the way I want to do it.

> Victron Smart Shunt. << I will look into how this works

You can plan all you want as I am trying, but it is truly a journey and not a destination. I can't wait for real world testing. Problem is my time is still divided as I have my own company to run and retirement is still down the road. Working remotely, however, has been easy!

If you read the suggestion about the temperature triggered heating pads, right at the battery, that may be the only option we have. Unless we travel out of the cold to someplace warmer and then can put the lithium out on the tongue.

Right now, no more $; maybe next year.