why i call Li fussy

pianotuna wrote:
3 tons, really only one thing keeps me from Li. https://youtu.be/009kRJKf9rg

PT, Due to the recent innovation of passive ‘pre-charge’ heating elements available in many of today’s LFP offerings, this below 0deg C charging concern (where a heated space is not possible) has been overcome - I would think that this should satisfy a wide majority of these outlier scenarios…As per the advent of dishwashers, I can sense that the paradigm is in the midst of another shift…

3 tons

Even with cold temperatures, you would probably do better with LiFePO4 with heaters than lead acid. You get all the benefits of LiFePO4, but you also avoid the capacity loss of lead acid in cold weather, at -30C lead acid only has 1/2 it's normal capacity - which I guess means you can only use 1/4 of the nameplate capacity.

3 tons, really only one thing keeps me from Li. https://youtu.be/009kRJKf9rg

RLS7201 wrote:
I still don't get it, with Li batteries.
The cost is outrageous.
They don't tolerate the cold. My wet cell deep cycle batteries live behind my front bumper and have worked perfectly down to -15F.
Additional devices must be purchased and added into the charging system. I.E. BMS, DC to DC chargers, etc.
4 100 amp GC batteries cost about $400 and last me 5-6 years. That's less than $100 a year for batteries.
We spend the winter months near Quartzsite on BLM property with 500 watts of solar. generator only runs for microwave and hair dryer.
Yeah, Li batteries charge faster, thus the DC-DC charger to protect the alternator. They weight less but that's not an issue for my coach.
For the additional cost of Li batteries, I wouldn't get any more service.
Flack jacket on

Richard

no need for a flack jacket, price wise your wrong, you have effectivly 100 ah usable power in four 100 amp GC batteries, so that would be 1 Li battery which would be about what 400 in the US? we will say 500 and we will even up it to two of them to double your capacity you can use.. thats 1000.00 and an aproximat life span of 20 years thats 50 bucks a year so half the cost. you dont need a dc to dc, I have never had my truck charging a battery yet , thats what the solar panels are for, I am just looking at one for my camper though as I do a lot of off season camping and dont have a lot of space for batteries. for the temp you are probably right, you could use them down to -13ish to draw power but cant charge till your up around -32 so if you are camping in that then ya your better off with the lead acid batteries, but having said that if you can move the batteries into the heated interior of the rv (which you can with Li as there is no offgasing and can be in any position) then that is all fixed, you can use them at -50.

Steve

…For those who may have missed it, be advised that the LFP boat has done left the dock - lol

Almot wrote:
Temps below freezing is a no-no when charging Li..

Seems like you'd have to be in some pretty cold weather for the batteries themselves to actually be that cold.

RLS7201 wrote:
I still don't get it, with Li batteries.
The cost is outrageous.
They don't tolerate the cold. My wet cell deep cycle batteries live behind my front bumper and have worked perfectly down to -15F.
Additional devices must be purchased and added into the charging system. I.E. BMS, DC to DC chargers, etc.

Temps below freezing is a no-no when charging Li. I think Battleborn allow few degrees below freezing, but most brands don't. Discharge and storage of Li down to 0F is fine.

Li cost in dollars per cycle is now lower than any other battery type on the market. BMS are inlcuded with drop-in Li, some users choose to buy cells and attach BMS - to save money.

pianotuna wrote:
time2roll,

Yes the bms keeps the batteries in balance--but what if a large load draws more than the rating on one of the bms of a 3 x 100 amp-hour bank? Potentially that could shut down one battery and then the other two might over load as well? I am just speculating.

Yes of course. You would not build something where it was ordinary to open a fuse any more than overload a BMS. This would generally only happen during a fault in which you would want to cut power.

I read about plenty of large off-grid home systems and this is not an issue.

With all the power you seem to be contemplating I will suggest to ebay that 12v inverter and go 24 or 48 volts.

Tom_M wrote:

pianotuna wrote:
Tom,

Show me a bms that allows a draw of 240 amps from a 100 amp-hour battery?

My future bank will allow 9600 amps. Not that I'll ever use that amount of current.

Your needs certainly are out of the ordinary. I have a 170ah Renogy drop-in lithium with built in BMS that I purchased two years ago from Walmart for $970 plus tax. I'm never in a situation where the battery temp will drop below 32F. I have 400 watts of solar and in two years may have run my generator 6 times to charge my battery after a couple of cloudy days. This does not include times that I run the generator to use my microwave or A/C. I don't have to do anything to the system. About the only thing I have to do is turn my inverter on when needing 120 volt power.

One who’s on a mission to find anomalies, tends to be able to find one behind every tree.

3 tons

time2roll,

Yes the bms keeps the batteries in balance--but what if a large load draws more than the rating on one of the bms of a 3 x 100 amp-hour bank? Potentially that could shut down one battery and then the other two might over load as well? I am just speculating.