Travato LiFePO4 Battery Install

[eric1514]

Makes sense, thanks.

Eric

[gerrym51]

I have a question .


as had been mentioned lithium batteries plate when charging below 32 degrees.

it has been also said that this can be avoided by heating the battery.

However how much battery power is used to heat a battery and keep it above 32 degrees.

if your piugged in probably no problem. if you have an 'engine generator' or just a regular alternator and engine running probably no problem.

however say your van's sitting and only has a solar panel? based on tank heaters i know about they use a lot of dc amps.

say it's at night and solar panel not producing?

say your using your lithium batteries in colder weather overnight. are the battery heaters working even if no charging?

just wondering about these lithium batteries using up precious energy for warming in cold weather.

i know lithium can be discharged below 32.ok

[avanti]

I don't think there would be any need to KEEP the batteries above 32 degrees, simply to warm them up in preparation for charging. Most sources claim that it is OK to draw from cold Li batteries. Moreover, very likely the batteries would self-warm during charging. So, wouldn't all that would be needed be a heating pad that raises the battery temperature immediately prior to a charge cycle? I don't see this as an issue, since by definition an external power source would be available at that point. So, the only downside is a delay before the charging begins.

Am I confused?

[markopolo]

Not quite on topic ... but, I keep hoping to see a 4 year update from Technomadia to see if the loss of capacity has continued.

3.5 year update here: Living the Lithium Lifestyle – 3.5 Year Lithium RV Battery Update | Technomadia

[gerrym51]

Originally Posted by avanti

I don't think there would be any need to KEEP the batteries above 32 degrees, simply to warm them up in preparation for charging. Most sources claim that it is OK to draw from cold Li batteries. Moreover, very likely the batteries would self-warm during charging. So, wouldn't all that would be needed be a heating pad that raises the battery temperature immediately prior to a charge cycle? I don't see this as an issue, since by definition an external power source would be available at that point. So, the only downside is a delay before the charging begins.

Am I confused?

this is the relavent power blurb from a rv tank warmer-

Additional wiring Instructions ONLY for 12 Volt DC Tank Blankets:

The 12 volt DC heaters use from 5 amps to 11 amps of current depending on the model. The DC Tank Blankets comes with 5 feet of #14 wire attached. The National Electrical Code standard rating for 14 gage copper wire is 15 amps. If you need to add additional wiring, then be certain to use 14 gage copper wire when wiring the tank blanket to the vehicle. Also, be certain that this wiring is connected to a 15 amp fuse in the vehicle and that if a toggle switch is used to control the power to the Tank Blanket that it is also rated for 15 amps capacity. Proper wiring is important, you must use the appropriate size connecting wire for the application, use 14 gage or heavier wire.

- See more at: Tank Blanket - 20 Gallon, AC - Twenty-six Eleven Llc 61002 - Holding Tank Accessories - Camping World


as you can see these things use from 5-11 dc amps per hour if not plugged in-therefore my question-just wondering

[Davydd]

I may be the only one with lithium ion batteries that has camped boondocked for four straight days all the time day and night below freezing and the lowest night at 5 degrees F. There is a great time lag for the batteries to drop in temperature when in use. The heating pads are rather small sandwiched between the cells. I haven't noticed the draw because driving tops the batteries in under an hour of overnight use. If you plug in then it is simple shore power will heat the battery heating pads. Shore power heats my much larger underfloor radiant heating pad that runs the length of the van. I can run all night with battery power. While driving the alternator is more than enough. Bottom line with 800ah of lithium ion battery it is a transparent non issue. At the other end - heat, we have been on the road for 124 days now and nearly 23,000 miles since January 26. Highest temperatures we have encountered is about 90 degrees and we haven't used our air conditioner yet. We have not stressed our batteries in that regard.

[gerrym51]

Originally Posted by Davydd

I may be the only one with lithium ion batteries that has camped boondocked for four straight days all the time day and night below freezing and the lowest night at 5 degrees F. There is a great time lag for the batteries to drop in temperature when in use. The heating pads are rather small sandwiched between the cells. I haven't noticed the draw because driving tops the batteries in under an hour of overnight use. If you plug in then it is simple shore power will heat the battery heating pads. Shore power heats my much larger underfloor radiant heating pad that runs the length of the van. I can run all night with battery power. While driving the alternator is more than enough. Bottom line with 800ah of lithium ion battery it is a transparent non issue. At the other end - heat, we have been on the road for 124 days now and nearly 23,000 miles since January 26. Highest temperatures we have encountered is about 90 degrees and we haven't used our air conditioner yet. We have not stressed our batteries in that regard.

i'm trying to figure out why an inverter left on overnight would empty 400 amp hours of lithium batteries-hence my question about the heaters

[Davydd]

Our typical overnight 16 hour stay with inverter on will only use about 160-200 amps draw. If we cook we will use more. Keurig coffee in the morning takes out about 20 more amps. It is all made up in about 40-60 minutes of driving with the second alternator. With 600ah to tap we have a lot of reserve. On our current trip not plugged into shore power we have only stayed a maximum of two days without driving. If we even stayed longer we would be driving around during the day as we just did in our Acadia NP stopover. That's why we have a B - to drive and drive lot.

[gerrym51]

Originally Posted by Davydd

Our typical overnight 16 hour stay with inverter on will only use about 160-200 amps draw. If we cook we will use more. Keurig coffee in the morning takes out about 20 more amps. It is all made up in about 40-60 minutes of driving with the second alternator. With 600ah to tap we have a lot of reserve. On our current trip not plugged into shore power we have only stayed a maximum of two days without driving. If we even stayed longer we would be driving around during the day as we just did in our Acadia NP stopover. That's why we have a B - to drive and drive lot.

Davydd-that's you. you can't help talking about -YOU-lol

[Davydd]

Originally Posted by markopolo

Not quite on topic ... but, I keep hoping to see a 4 year update from Technomadia to see if the loss of capacity has continued.

3.5 year update here: Living the Lithium Lifestyle – 3.5 Year Lithium RV Battery Update | Technomadia

Some caveats. They had capacity loss but it was something like 25% not dead batteries. In their same practices they had destroyed AGM batteries in just a year's time.

They had an older generation of battery and no sophisticated BMS to monitor them. They never knew individual cell voltage and temperature.

It appears they had them in an unconditioned inside compartment that severely overheated I think.

They spent time in the desert southwest in the summer which is the most severe test of all. In effect they did everything as abusive as possible. I might be concerned if I lived in the south but as a northerner I don't see it as an issue.

BTW, the Tecnomadia couple are frequent partisans and moderate a Facebook for fulltime RVers. I don't know if they have mentioned anything there. I don't follow it that closely.

[Davydd]

Originally Posted by gerrym51

Davydd-that's you. you can't help talking about -YOU-lol

Gerry, You are the one that questioned blowing through 400ah of lithium ion battery overnight. I simply gave you my detailed experience which refutes your supposition. Either that, or if you are referring to Roadtreks, why don't you ask them? If your supposition is true, they have serious problems.

[booster]

Not lithium information, but as a point of reference. Davydd mentions using in the range of 200+AH in a 16 hour stayover, and driving every two days (which he would have to do or run out of power at that usage).

We just got back from 4 weeks out, with about 2/3 of the time without shore power. We were 6 days straight in Zion park without moving the van, relatively sunny site. We used only the 260AH batteries and were never more than 10% down, and that would be in the morning. Even if it had been cloudy the whole time, we would have been able to go at least 3-4 days at our usage and cloud reduced solar. We used 35-50AH per day, depending on weather mostly. Frig and fans when 98* takes some power.

The point is that if the Ecotrek 200 and 400 eat power like Davydd's does, so the solar can't keep up, they are going to go flat pretty quickly, and will go down over time if let sitting with stuff on.

[markopolo]

Originally Posted by Davydd

Some caveats. They had capacity loss but it was something like 25% not dead batteries. In their same practices they had destroyed AGM batteries in just a year's time.

They had an older generation of battery and no sophisticated BMS to monitor them. They never knew individual cell voltage and temperature.

It appears they had them in an unconditioned inside compartment that severely overheated I think.

They spent time in the desert southwest in the summer which is the most severe test of all. In effect they did everything as abusive as possible. I might be concerned if I lived in the south but as a northerner I don't see it as an issue.

BTW, the Tecnomadia couple are frequent partisans and moderate a Facebook for fulltime RVers. I don't know if they have mentioned anything there. I don't follow it that closely.

That's why I'm hoping they post a followup. It should give a better idea of what to avoid or what to do or what to buy to make the batteries last longer.

They looked to be breaking even cost wise as of that last update:

So overall while we aren’t likely to see much of a lifetime cost advantage, the cost question is basically a wash for us.

[avanti]

Originally Posted by Davydd

Keurig coffee in the morning takes out about 20 more amps.

Don't know what you mean by "20 amps". A cup of Keurig coffee takes well under 4 A/h (less for multiple consiecutive cups). So with any reasonable battery, the Keurig demands aren't really overly significant. People who have Keurig issues usually have too-small an inverter.

[gerrym51]

Originally Posted by avanti

Don't know what you mean by "20 amps". A cup of Keurig coffee takes well under 4 A/h (less for multiple consiecutive cups). So with any reasonable battery, the Keurig demands aren't really overly significant. People who have Keurig issues usually have too-small an inverter.

i often see people intermingling DC AMPS and AC AMPS as if the same.

of course you don't use the Keurig for the full hour

wouldn't 4 AC amps be 40 DC amps on an hours basis

[ptourin]

You coffee people are confusing me - but I'm not a coffee drinker <g>...
The Keurig 2.0 draws 1740W; the Mini Plus draws 1425W. If you run them through an inverter that runs at around 85% effeciency, your total wattage draw goes up to around 1750W. You need a big inverter - like Avanti said!

If your batteries are sitting at around 12.5V, that's going to be about a 135A draw. High current - but the Mini Plus makes a cup in around 2 minutes. Two minutes of 135A is (2/60)*135 Ah, or 4.5 Ah - like Avanti said.

Same with a hair dryer, or the microwave - it's a lot of current, so the inverter needs to be big. But if you don't run it for a long time, it's not a lot of amp-hours. So if Davydd says he figures on 20 amps for coffee, he probably means amp hours, and they both drink 2 cups - or some such.

[avanti]

Those Keurig current specs are maximum--you only see them while the water is being heated. The average current draw is lower. Over the course of brewing a cup, the total consumption is around 40 watt/hours (by actual measurement), which is something like 3.2 A/h at 12V.

[Davydd]

I was just guessing on that. After getting up, brewing the coffee, hot water, lights, etc we may blow thru 20 amps before taking off. Then to think about it 10 of those are the normal overhead. Basically I was pointing out that going thru a 400ah lithium ion battery is nearly impossible overnight. I have quite a standby load:

The 2800w inverter
The Silverleaf control screen
The 6.8 cf two door ref/freezer
Two always on wifi routers
Wilson cell booster
Four devices plugged into USB ports
Trik-L Charger
Probably more lighting than the average B though all LED
And all the other usual standby stuff

[Jostalli]

Originally Posted by Davydd

I was just guessing on that. After getting up, brewing the coffee, hot water, lights, etc we may blow thru 20 amps before taking off. Then to think about it 10 of those are the normal overhead. Basically I was pointing out that going thru a 400ah lithium ion battery is nearly impossible overnight. I have quite a standby load:

The 2800w inverter
The Silverleaf control screen
The 6.8 cf two door ref/freezer
Two always on wifi routers
Wilson cell booster
Four devices plugged into USB ports
Trik-L Charger
Probably more lighting than the average B though all LED
And all the other usual standby stuff

Why does the inverter need to be on at all times? Why wouldn't you design it so most devices/appliances operated on 12V so you could leave the noisy, power sucking inverter off when not needed?

[booster]

Originally Posted by Jostalli

Why does the inverter need to be on at all times? Why wouldn't you design it so most devices/appliances operated on 12V so you could leave the noisy, power sucking inverter off when not needed?

Well stated, and exactly the point that several of us have made in the past. It seems inordinately impractical to take a native 12v system and run it through an inverter all the time to get 110 volt, just so you don't have to get some 12v adapters, etc. The micro and the air conditioning are about all we have on 110v, except for short run hair dryer or curling iron. We turn on the inverter to run those things (not AC) when we need it instead of using power all day and night. We use about 1/6 of the amp hours that davydd does. We don't drink coffee, so I get to stay out of that discussion