Lithium Titanate

BFL13 wrote:
Not clear if this is the same thing as Lithium Titanate (?)

Nope it is LiFiPo4 with a heater added.

Not clear if this is the same thing as Lithium Titanate (?)

I see "Canbat" LFPs where one version has a heater in it. and costs way more than the same (?) batt without the heater.

"In cold temperatures, the BMS ( battery management system) disconnects from the cells to protect your battery. Prior to charging, the built-in heating systems draw power from the charger in order to heat up the battery."

http://www.wegosolar.com/categories.php?category=Deep-Cycle-Batteries/CAN-BAT-Lithium

dup.

I live in Regina and service the south west, south east and north in large circles.

Starting a generator below -25 is pretty difficult. That's another reason for SiO2. I have remote electric start--but I've so far killed 2 batteries. I'd love to add a trik-l-start--but they refuse to ship to Canada.

pianotuna wrote:
I tune pianos in rural SK. Sometimes that has been at -37 c and without shore power. I will NOT run a generator while sleeping.

My RV is HIGHLY modified and I had 875 amp-hours of battery bank.

Moving Sue and Photo Mike have boondocked at -40, so I'm not a record holder.

ok so your using it in a comercial mannor so ok you make sence. and them moving, I have been in the cold when traveling and at that temp its just not fun, you cant sleep because its so cold it is just miserable, at -40 I would pull into a hotel.

In your case if you have a generator and did decide to go li. I would use your generator to power a battery warmer for a short period then fire up the furnace. you could get that 16 Cell set up I am looking at and have 1120AH so about 1000 usable. but ya, spending the money on the Sio2 in your case you can use it as a company write off so it might be the way to go. how does there capacity change with cold?

Which part of Sask are you in, My cousin farms in Goodsoil.

Steve

I tune pianos in rural SK. Sometimes that has been at -37 c and without shore power. I will NOT run a generator while sleeping.

My RV is HIGHLY modified and I had 875 amp-hours of battery bank.

Moving Sue and Photo Mike have boondocked at -40, so I'm not a record holder.

pianotuna wrote:
Steve,

You missed my point entirely.

Storing at -40 how do you run the furnace with no 12 volt power because you can NOT draw on an LiFePo4 for the 2 to 3 hours the furnace needs to run.

Plus my brothers experience was that storing at -40 killed an li battery. I do not know which Li chemistry it was.

the chemistry is the big thing like I said (I didn't miss the point) you can warm them with low draw at that temp you can use full draw on a LiPhO4 at -20. persoanly if I found a need to go camping at -40 I would have a normal Lead acid battery that I could just put a 12V battery warming blanket on to to prewarm them to the point there above -20 then kick on the furnace, but thats getting a little crazy isnt it?

what kind of camping are you going to do at -40? (Im being serious now) I grew up in Edmonton and area so I know what the cold is about and I dont know anyone who willing went camping that cold, -10 to -20 maybe. we used to go skidooing in the mountians but it was never that cold, Im just having a hard time seeing what your doing for camping at -40 expecialy since no camper that I have seen is rated below about -17. it would be crazy the amount of propane you would burn and still be cold, or do you just use that number because some times it gets that cold and some one could in theory want to go camping?

Steve

Steve,

You missed my point entirely.

Storing at -40 how do you run the furnace with no 12 volt power because you can NOT draw on an LiFePo4 for the 2 to 3 hours the furnace needs to run.

Plus my brothers experience was that storing at -40 killed an li battery. I do not know which Li chemistry it was.

I notice a lot of people trying to compare charging time between the LI, Sio2 and LA, you cannt put Li in that comparason as the limitation 99.9% of people are going to run up against is the size of the charger. there is no adsorption mode on the Li, well maybe a min or two at the verry end it is all bulk other wise at a 1C rate and that is artificial and introduced by the BMS LiphO4 is actualy a 4 to 7C rate but who is every going to use that so why not make them last a little longer. that means if you have a 280AH 12V battery you could have a 280amp charger and charge that bank in about an hour, now I dont know anyone who has a charger that big but with the new 3in1 setups that combine solar and your Dc to Dc charger and ac charger in one it could be possible to have all three going in an emergency, but that is extreem. so lets go with a battery bank of around 200 usable ah, which would be two Li batteries or 4 6VGCor 250ah of Sio2 what ever that is, lets say you have a 75 amp converter, and you have used 150 amps. you could fully charge the Li bank in 2 hours, but I do know you are not charging the others anywhere near that fast to 100% if they would even handle a 75 amp input with out it being reduced.

Steve

pianotuna wrote:
Steve,

It is a concern if you store at -40. How do you get the "living space" warm without a usable battery bank?

the company I was writing to has a 100 amp-hour LiFeP04 with BMS drop in for $400 Canadian. Their store is at Lac La Biche Alberta

there is no concern for having a Li battery sitting not being used at -40 it is only charging below 0 that is fround upon and can cause dammage. you can still discharge them much lower. the neet part of the Lit you were showing is you could charge it a fair bit colder but the energy density made them even lighter and smaller than LFP. most list there discharge range from -20C to 70C but for storage it isnt an issue. they use them in powersport (skidoos) much colder and sellers just recomend a short crank to "prewarm" the battery. in a RV you could just turn on the furnace and not use high amp draws like microwave and such untill the interior is warm, or if you had a low draw batery warmer turn that on for a few min then start the furnace. personaly I just wont camp at -20 anymore ;)

ya for someone that can't DIY or just doesnt want to the prices are getting amaxing. My 235AH 6V cost me 300 each so still a bit cheeper upfront but when you looks at 600-800 cycles compared to 4000-7000 cycles depending on the type of cell they are using thats not bad.

right now I can get four 280 ah cells for 280.00 + shipping that will make a 280ah 12v battery, the BMS can be had as low as 20 bucks , but a good quality Daly runs about 140.00 cdn but that will control up to 8 cells and active ballance and such so that is what I would buy for a 560AH 12V battery. their 4 cell one is about 100 bucks.

if you are not going to be pulling high amp loads you just need to tape then togeather and put in a box you can build or buy, if you are going to be running hgh draws then would box must also hold them snug togeather so not alot to them realy. the cells come with bus bars and such. ther only issue is the actual shipping cost of the cells. it varries from 200 to 1000 bucks of a pack of 4. I have found some places that include shipping and I think it was 1600 cdn for 8 of the 280 ah cells. so I figured I would be around 2000 tax in to build a 560AH battery with 90% usable ah, or 1200 to replace my four 6V. I have found one that is 2200 for 16 cells including shipping so that is a option also, I could put a 840AH battery in the 5th wheel and a 280ah in the camper. so for me it is going to be a money desision come spring unless shipping comes down a lot, or with covid happening if I decide to use the camper more than the 5th this year maybe Ill put it off another year and see what prices do.

Steve