Ballistic EVO2 Motorcycle Batteries
04-27-2012, 11:24 PM
#21
Boost Pope
iTrader: (8)
Join Date: Sep 2005
Location: Chicago. (The less-murder part.)
Posts: 33,046
Total Cats: 6,607
That part has to be true. If Ballistic is advertising individual-cell balance charging on their 8-cell and higher packs, they aren't being honest. In order to balance each cell in a 16-cell pack individually, the balance plug would require 17 leads (1 positive for each cell plus one common ground).
Fortunately, this is not a problem, as cells in parallel tend to mutually self-equalize.
For any given pack voltage, the number of cells in series will always be a constant. In the case of a 13.x volt pack, there will always be 4 cells in series. Additional capacity (in Ah) is thus created by paralleling groups of 4 cells. So an 8 cell pack will always be 4S 2P, a 12 cell pack will be 4S 3P, 16 cells will be 4S 4P, etc.
Thus, regardless of the total number of cells in the pack, the number of balance leads will always be 5 (the total number of end-points of a series string of 4 cells.)
This is how all LiFe BMSes are configured.
Reply
0
0
04-28-2012, 12:15 PM
#23
Boost Pope
iTrader: (8)
Join Date: Sep 2005
Location: Chicago. (The less-murder part.)
Posts: 33,046
Total Cats: 6,607
I still find this whole concept kind of hard to grasp.
I mean, they obviously work. We have proof of that.
It's the concept that, as you said, you can just throw one into a car with a 65 amp alternator and series-charge it t your heart's content with no internal balancing that seems odd.
That, and the fact that they apparently don't support an internal LVC to prevent the thing from being destroyed by dark currents. I suppose that would be difficult, given that you'd need a switching device that was capable of passing starter current and yet didn't require gobs of power to operate.
I mean, they obviously work. We have proof of that.
It's the concept that, as you said, you can just throw one into a car with a 65 amp alternator and series-charge it t your heart's content with no internal balancing that seems odd.
That, and the fact that they apparently don't support an internal LVC to prevent the thing from being destroyed by dark currents. I suppose that would be difficult, given that you'd need a switching device that was capable of passing starter current and yet didn't require gobs of power to operate.
Reply
0
0
07-02-2012, 03:38 PM
#27
I've been running a 12 cell in the SSM car. I'll probably upgrade to the 16 cell soon. The 12 cell has trouble cold starting the 1.8 on an AEM with the stock crank trigger wheel (takes 8-10 seconds to catch). If I could get the 12 tooth wheel working, it'd be fine on the 12 (maybe even the 8,) but as is, it's a little scary if it'll start before the battery stops cranking.
Reply
0
0
07-02-2012, 04:30 PM
#29
For a DD, if you're really pedantic enough about weight to get something this tiny, I'd definitely go no lower than the 16 cell. It's ~1 pound heavier than the 8 cell, and gives you way more cranking power. In a perfect world, you could get away with the 8 cell as long as you're above probably 60 degrees for 99% of your cranks, but I wouldn't want to risk it.
The big problem with these batteries for DD is just the lack of amphour capacity. They're much better than lead acid or gel batteries for providing more CCAs for longer, but when they cut out, they cut out dead. They don't actually have that much reserve capacity. So, you leave your lights on for a little while, it'll die, and way sooner than even a small lead battery.
The big problem with these batteries for DD is just the lack of amphour capacity. They're much better than lead acid or gel batteries for providing more CCAs for longer, but when they cut out, they cut out dead. They don't actually have that much reserve capacity. So, you leave your lights on for a little while, it'll die, and way sooner than even a small lead battery.
Reply
0
0
07-02-2012, 06:26 PM
#30
Elite Member
Join Date: Jul 2005
Location: Anacortes, WA
Posts: 2,478
Total Cats: 144
For a DD, if you're really pedantic enough about weight to get something this tiny, I'd definitely go no lower than the 16 cell. It's ~1 pound heavier than the 8 cell, and gives you way more cranking power. In a perfect world, you could get away with the 8 cell as long as you're above probably 60 degrees for 99% of your cranks, but I wouldn't want to risk it.
The big problem with these batteries for DD is just the lack of amphour capacity. They're much better than lead acid or gel batteries for providing more CCAs for longer, but when they cut out, they cut out dead. They don't actually have that much reserve capacity. So, you leave your lights on for a little while, it'll die, and way sooner than even a small lead battery.
The big problem with these batteries for DD is just the lack of amphour capacity. They're much better than lead acid or gel batteries for providing more CCAs for longer, but when they cut out, they cut out dead. They don't actually have that much reserve capacity. So, you leave your lights on for a little while, it'll die, and way sooner than even a small lead battery.
Having said that The Heavyer NA starter will crank the car much more sucsessfully than an NB starter on a weak small battery.
Reply
0
0
07-02-2012, 06:53 PM
#31
Im running a 12 Cell It has way more cranking amps than any other small battery I have tried. and will crank the car multiple times roll up my electric windows with the car off etc.
Having said that The Heavyer NA starter will crank the car much more sucsessfully than an NB starter on a weak small battery.
Having said that The Heavyer NA starter will crank the car much more sucsessfully than an NB starter on a weak small battery.
I had a 180ma constant current drain on my car when I first built it. I plugged it in around 10pm and the battery was down to 5V the next morning. Woopsie.
Reply
0
0
07-03-2012, 02:30 AM
#32
Boost Pope
iTrader: (8)
Join Date: Sep 2005
Location: Chicago. (The less-murder part.)
Posts: 33,046
Total Cats: 6,607
I wonder:
Since we are talking about spending large quantities of money on lightweight batteries, I wonder why neither Ni-Cad nor NiMh have been mentioned?
Both are cheaper than most (all) of the present-day lithium technologies, and permit the use of rather simpler charge controllers.
Since we are talking about spending large quantities of money on lightweight batteries, I wonder why neither Ni-Cad nor NiMh have been mentioned?
Both are cheaper than most (all) of the present-day lithium technologies, and permit the use of rather simpler charge controllers.
Reply
0
0
Thread
Thread Starter
Forum
Replies
Last Post
