Are some of these top makers (Limitless / jy) running the cells at full charge? I have been reading and studying how these work as well. It would make sense why they rate the amps/wattage so high per ah if they run whatever cells are inside at full capacity.
I'd guess it's similar to power ratings on anything where they assume that few people will ever see much more than half rated power out of an amp and even that not for long due to impedance curve and the dynamic nature of music. That said, the LiFePO4 cells that they use are likely 30C rated so they'll deliver 10X their amp hour rating in burst current.
Okay. This has been a great thread and with the help of y'all ready to get this going. There isn't to much to it. Youtube and google just made things difficult to decipher. I'll knock out the agm and add another parallel line just to be sure and not over stress the bank (cells) so 24 cells and 6s4p 160ah. Now if I can just get a group by and drive down the cost of cells, that'd be great.
That's the spirit, go big or go home. Feel free to bus them whatever way you want. A couple of the Chinese suppliers had some various bussing solutions which weren't quite cost effective as cutting up your own bar but may be a lot easier to work with and give you more flexible options. The biggest price break per cell was just buying enough to get into sea/freight shipping. Smaller orders would have had to ship express.... at your door in @ 5 days but over double the cost of sea shipping which was already pretty high. Like I said, I'm really happy with the company I ordered them from so stick to them
Not sure how thwy are running their cells. But they aren't running bms's on them. I have no idea how they get their ah ratings of 15ah for a 3k system. They must be running the cells hard for those ratings, As u stated. And yep they'll die or worse.
A123 32113 cells are 30C rated and have been tested to do even a little more. I know one of those tailor made lithium companies uses those, the rest likely use something similar/comparable. So indeed, a 15AH battery could deliver 450A. I think your big issue there is the charge rating of only 5C IIRC, meaning charging with greater than 150A would probably hurt them far faster than quick burst draws. Mind you 15AH is still 15AH so you don't have that much on tap, just what you have you can get a lot of very quickly.
The initial bank I was planning was those cells, I'm glad I jumped ship into the LTO.
Is ur amp rated for below 1ohm? I am just curious as mine is rated to 1 ohm but I'll be running a .67 ohm load when I get my third sub.
Rated 1 ohm and "stable into .5 ohm dynamic" or somesuch. Again, they figure at .5 ohm nominal the amp will probably never see below .7 or so anyway.
I really wanted this thread to be informative and a knowledge base. A few of us have done a lot of research and now some testing. The guys who sell 1200$ 40AH LiFePO4 banks aren't likely to chime in and tell us anything, in fact the main reason I did this myself is that I couldn't get a straight answer out of any of the 3 companies I tried to talk with about them. If i wasn't so busy with my real work and other projects I'd have kept my lips shut and would be building banks for resale myself probably charging about 2000$ for the 240AH size I'm using here or thereabouts. The catch would be to figure that you would have a certain number of duds or failures from abuse that you'd have to eat the cost of and charge a price accordingly. If you can wait a month and a half to get the cells, take a couple days to make your own bus bars and assemble sure you can save some money, you want the work done and delivered in a few days, pay up. In fact, if anybody is impatient I'll sell the bank I have sitting here for my brother right now for 2000$.
