LiFePO4 charging in cold weather

[triplethreat]

I've been working with electrons (and holes) for over 40 years so it wasn't unfamiliar territory.

Me too. Started my apprenticeship in early 1977 and topped out the end of Dec, 1980. Back then, it was a 4 year apprenticeship and they counted OJH (on the job hours). You needed 8000 hours of OJH and I was fortunate enough to get some overtime in during my apprenticeship training, and those hours counted also. Now days, it's a 5 year apprenticeship program.....I guess we were just smarter and learned quicker back then.

 

[Scott'n'Wendy]

I've been working with electrons (and holes) for over 40 years so it wasn't unfamiliar territory.

Black holes? Worm holes?

 

[triplethreat]

Black holes? Worm holes?

He's referring to the "hole flow" theory vs. electron flow theory. Those holes would be much too small for a worm to fit in!

 

[coglesby]

He's referring to the "hole flow" theory vs. electron flow theory. Those holes would be much too small for a worm to fit in!

Not exactly. Hole and electron flow in semiconductor devices. Current in conductors is only electron flow.

 

[coglesby]

Me too. Started my apprenticeship in early 1977 and topped out the end of Dec, 1980. Back then, it was a 4 year apprenticeship and they counted OJH (on the job hours). You needed 8000 hours of OJH and I was fortunate enough to get some overtime in during my apprenticeship training, and those hours counted also. Now days, it's a 5 year apprenticeship program.....I guess we were just smarter and learned quicker back then.

6 years of electrical engineering college and 40+ years semiconductor device physics and circuit analysis in a semiconductor manufacturing facility. Here’s what I did for anyone interested

 

[coglesby]

Black holes? Worm holes?

Electron vacancies

 

[Scott'n'Wendy]

Here’s what I did for anyone interested

I would still have that now unused piece of #6 connected to the converter

 

[coglesby]

I thought about that but that would render the battery cutoff switch ineffective. On the other hand I’m not sure I’ll ever even use it but it still functions as intended the way I wired it.

 

[coglesby]

I would still have that now unused piece of #6 connected to the converter

I thought about that but that would render the battery cutoff switch ineffective. On the other hand I’m not sure I’ll ever even use it but it still functions as intended the way I wired it.

I do like that now the converter is still connected to the battery when the battery is disconnected from the power distribution panel

 

[Butcher]

You had to do down the hole hole. Now you just blew up this thread.

 

[NowaRAMguy]

So should one move the battery location to the basement of a 5VR from the front bay when converting to LiFePO4 since they can’t be charged below freezing?

I just added heaters to my batteries on a thermostat. I don't have the particulars handy, but they work rather well.

 

[Indy Tim]

I just recently changed over to lithium. I went the other way. Moved the charger to the battery

I am doing the same. Did you put a fuse or breaker in between the converter/charger and the battery? Where/how did you mount the converter? Thanks

 

[coglesby]

I upgraded to 75a converter so I used a 90 auto reset breaker on the output of the converter. I used the existing location for the converter so I just used the existing mount.

 

[Indy Tim]

I upgraded to 75a converter so I used a 90 auto reset breaker on the output of the converter. I used the existing location for the converter so I just used the existing mount.

Thanks. Do you remember the brand of breaker? I looked on Amazon and there are many but most have bad reviews.

 

[coglesby]

90A auto reset breaker

Amazon.com

What is not shown is I added a victron smart shunt between battery and union and a chassis ground from the load side of the shunt

 

[orbiker]

It's going to have to get pretty cold outside to chill the batteries down to 32* in the generator compartment if the rest of the rv is being used and warm.
Our Solitude has 4 100AH lithium batteries in a plastic storage box. Right now the batteries are at 52*F according to the temp sensor of the battery monitor. It's 57* in the water connection area and 44* outside. We are at the Oregon Coast ( at Hort Stevens Historic Area as camp hosts ) and it's been windy ( 10 -15 mph plus ).

The batteries stay close to 50* most of the time.
KEN

 

[coglesby]

It's going to have to get pretty cold outside to chill the batteries down to 32* in the generator compartment if the rest of the rv is being used and warm.
Our Solitude has 4 100AH lithium batteries in a plastic storage box. Right now the batteries are at 52*F according to the temp sensor of the battery monitor. It's 57* in the water connection area and 44* outside. We are at the Oregon Coast ( at Hort Stevens Historic Area as camp hosts ) and it's been windy ( 10 -15 mph plus ).
View attachment 494336
The batteries stay close to 50* most of the time.
KEN

Gets pretty darned cold at my land near Angel Fire, NM in the winter at 9000 ft above sea level. In fact it’ll be about 10 degrees F Sunday night and it’ll be even colder in February.

 

[Butcher]

My experience with cheap Chinese circuit breakers are no good. I can say, the 4 I purchased were all no good. Some had a huge voltage drop. Others would trip well under the rated amount. Some did not seem to trip at all. Lesson learned and they were all recycled. I got breakers on the AC side and fuses on the DC side.

I would be scared to think what an auto reset cheap Chinese circuit breaker would do. For me, if the breaker did it's job, I would think I got a problem. I would have to figure out why. Sometimes we know that we plugged in a consumer that uses too much power and that is the reason, but if you know you are within your limits, it breaks for a reason. Let me make that choice if I turn the thing back on.

 

[coglesby]

The one I bought was a Gloso which is a Taiwanese company. It had very high ratings on Amazon.

 

[triplethreat]

The one I bought was a Gloso which is a Taiwanese company. It had very high ratings on Amazon.

Just be careful, there are a lot of things on Amazon that have good ratings....but that doesn't make it 100% accurate or true. A random example of that is someone that buys a new tool of some sort. When it arrives it's all shiny and new, and was in a plastic bag. To them, it deserves a 5 star rating. Two weeks later when the tool breaks or fails to operate as it should, they return it to Amazon and either get a refund or another one sent to them........but they many times do not come back and update their previous 5 star post. I'm just sayin'