Energy What are your thoughts on PB vs LFP ?

I have found that during the winter months, maintaining a charge on the battery bank often required mechanical charging, and doing that with a small 5 HP engine an automotive alternator was the most efficient use of fuel.
You can't store AC power, so it makes the most sense ( to me) to be filling one's battery bank and drawing what little intermittent AC require through an inverter .
Since a battery bank is limited by it's size, the larger the bank the better.
If I had the resources I would have several different types of batteries and use them as a resource to prove their worth, comparing apples with apples . Every single one of my components pass through switches and meters so I know how each are performing .

 

Been busy working so been away for a while.

In the end when I weigh it all up, I am going LiFePo4. Too many advantages to overlook this tech. If it wasn't for the money angle I think most would be going this way.

Biggest single factor for me and the point that sways me over to this side of the fence is the fact the LiFePo4 battery pack can be run down to within 10% of empty and still be OK. Cherry on top is the pack can sit in that condition for extended periods and not have a harmful effect.

I think there is no clear answer though - depends on the specifics of the situation at hand.

 

Don't charge them up 100% and they will out last you.

 

yep agree. My plan is to charge up to 80% and take them down to 30% - so still only 50% of pack total amp hours usable - but increases cycles dramatically.

 

That is how I do it, I'm hoping I can get 30 years out of them but we will see. What brand of batteries are you going to use?

 

My 2 cents:

1) how many cycles do you get out of your cell phone before the battery goes south? 300-500? Why expect more from a lithium house battery?

2) heavy batteries are harder to steal

 

We are talking about LiFePO4 technology not Li-ion. You cell phone is Li-ion.

LiFePO4 batteries are safe and have an unknown life span (years) since they are new to the market, most companies estimate 2000-4000 cycles before they degrade to 80% of their advertised capacity. People are also finding that if they do not charge them to 100% it seems to extend the lifespan dramatically. They are relatively new to the market and it takes a lot of digging to find good information about them.

Regarding your second point, the LiFePO4 prismatic batteries usually come in 3.2v so it takes a bunch of them which would be more difficult to carry. Also, your common thief probably wouldn't even know what he was looking at if he saw them.

 

Or charge them one time when they are at less than +20F and you permanently damage them, you lose around 20% of capacity just charging them one time when they are too cold.
And they suffer from sever cold numbing, as they get below 40F you start loosing amps that you can pull out of them fast.

Then if they are charged when they are too hot, same thing, capacity damage. Charging them too hot, too many times can completely ruin them.
This is one of the main reasons I wouldn't want LiFePO4, even in new Mexico.
It's going to be too hot or too cold for them about 5 months out of the year.

If I was going to use lithium for off grid it would be a lithium nickel manganese cobalt oxide battery.

 

Mine are stored in our utility room which is concrete and underground so the temp is relatively stable around 70F.

 

That's pretty much what you have to do with LiFePO4 and will help lead acid last a good bit longer.