macribs
10 MW
- Joined
- Jul 22, 2014
- Messages
- 3,702
So making a 18650 battery, eh?
Well I got to start somewhere, so I might as well try to get a little help with things that are on me mind. I must say I am more then a little intimidated by the task at hand.
1: Starting with the basic, when making cells do I start by making blocks in series or parallel? For me it will be a 22s12p battery. Or maybe less cells if my currency keeps dropping.
2: I don't know if I should skip BMS or not. If I do skip BMS it will make creation of the battery pack a little less daunting, and I will save time on soldering. Do I ever need to balance charge the pack, or can I just charge it all up to say 4,1v?
3: I see different ways of making batteries. Some just use nickel strips and calls it a day. Others feel that nickel alone can cause voltage drop because of heat so the solder on copper wire or silver wire on top of the nickel. Is that overkill, or something worth doing? I am thinking most power possible from the battery, and if that trick will help me get more power out without heating battery it just might be worth it?
4: Choosing a brand and a model seems like a lot of work just to know what separates the brands and models apart. I've been reading up for some days now, but I must say I am a little cooked in the head now. So at the moment I am considering one of these; Sanyo NCR18650GA or Samsung INR-18650-35E. Then there are 20R , 25R and 30Q. Panasonic NCR18650B same as in Tesla, right? Kind of tempted to go with Sanyo or 35E from tumich.
Is there other cells that might give me higher C rate and more fun for repeatedly accelerations etc? Or are any of those from tumich a good choice?
5: Was planning to fit an on-board charger, like an Eaton APR48-3G. Do they have any way to regulate the charging, like a high voltage cutoff or must I personally keep my eye on the charging if I use this without BMS? I got really bad short term memory so putting me in charge of watching the voltage will end in pain and wasted money. How can I control high voltage cutoff without a BMS?
6: I see a lot of people are making pre-charge, I know it is beside the battery thread but for me it got to do with electricity so for me it is in the same alley. What does a pre-charge do? And should I use it?
7: Do people usually by a bit more cells then what they are building, to count for bad cells, bad welds, bad welder etc? I will use some recycled cells for trial and error on the spot welding. I mean for 264 cell pack how many could be bad - like 1-2% extra should be sufficient?
Forgot to mention that I got a QS 205, and I plan to pump 12-14 kw peak into that hub. The reason I decided to go 22s12p was to give each cell an easier life and get better C rate.
Some phrases might be worded wrongly, if in doubt you should assume I have no clue as to this topic. If I am mixing up words, thinking of this the wrong way or in any way don't make sense to you, let me know and I will try to explain. But I am in way over my head here
Well I got to start somewhere, so I might as well try to get a little help with things that are on me mind. I must say I am more then a little intimidated by the task at hand.
1: Starting with the basic, when making cells do I start by making blocks in series or parallel? For me it will be a 22s12p battery. Or maybe less cells if my currency keeps dropping.
2: I don't know if I should skip BMS or not. If I do skip BMS it will make creation of the battery pack a little less daunting, and I will save time on soldering. Do I ever need to balance charge the pack, or can I just charge it all up to say 4,1v?
3: I see different ways of making batteries. Some just use nickel strips and calls it a day. Others feel that nickel alone can cause voltage drop because of heat so the solder on copper wire or silver wire on top of the nickel. Is that overkill, or something worth doing? I am thinking most power possible from the battery, and if that trick will help me get more power out without heating battery it just might be worth it?
4: Choosing a brand and a model seems like a lot of work just to know what separates the brands and models apart. I've been reading up for some days now, but I must say I am a little cooked in the head now. So at the moment I am considering one of these; Sanyo NCR18650GA or Samsung INR-18650-35E. Then there are 20R , 25R and 30Q. Panasonic NCR18650B same as in Tesla, right? Kind of tempted to go with Sanyo or 35E from tumich.
Is there other cells that might give me higher C rate and more fun for repeatedly accelerations etc? Or are any of those from tumich a good choice?
5: Was planning to fit an on-board charger, like an Eaton APR48-3G. Do they have any way to regulate the charging, like a high voltage cutoff or must I personally keep my eye on the charging if I use this without BMS? I got really bad short term memory so putting me in charge of watching the voltage will end in pain and wasted money. How can I control high voltage cutoff without a BMS?
6: I see a lot of people are making pre-charge, I know it is beside the battery thread but for me it got to do with electricity so for me it is in the same alley. What does a pre-charge do? And should I use it?
7: Do people usually by a bit more cells then what they are building, to count for bad cells, bad welds, bad welder etc? I will use some recycled cells for trial and error on the spot welding. I mean for 264 cell pack how many could be bad - like 1-2% extra should be sufficient?
Forgot to mention that I got a QS 205, and I plan to pump 12-14 kw peak into that hub. The reason I decided to go 22s12p was to give each cell an easier life and get better C rate.
Some phrases might be worded wrongly, if in doubt you should assume I have no clue as to this topic. If I am mixing up words, thinking of this the wrong way or in any way don't make sense to you, let me know and I will try to explain. But I am in way over my head here