LI-ghtcycle
10 MW
Ok, I have done a lot of searching and reading the last week or so, and I just want to run a few ideas by you folks. I think I understand about %75 of what I have read, so before I take the plunge, I just want to know I'm not about to break my neck in too shallow of intellectual water! :lol:
Question #1)
First off, I have been less than delighted with the Dewalt charger, it works, I guess ... if it HAS too ... Reminds me a lot of the "man's prayer" from Red Green.
I learned from my reading that it's generally accepted that 3.6V per cell of A123 batteries is a solid charge, and since the Dewalt charger isn't very consistant at balancing, short of opening up a pack of 8 (28v DC9280) cells and testing each one, would it be safe to say that if I have a total voltage of approximately 28.8+ on the pack (I can usually get each pack to show at least 29v, some as high as 29.7) by simply "re-charging" again after the first "charge" when all the LED's Stay solid.
It would seem that the charger goes Idle once all 3 lights are solid, so I don't think leaving it in the charger longer makes a bit of difference, UNTIL you take them out again, and put them in again for another 5 mins. or so. Using this method, I have been able to get most of the packs to hit about 27.6-27.9 on the initial charge, and then reach high 28's- low 29's on subsequent 5 min. "top-up charges". Almost all the batteries (I have 8) take 2 top-up charges, but some take 3-4 short top-up charges to reach this level.
Is it safe to say if I have 29v+ on an 8cell A123 pack that they are going to be at or really close to 3.6v?
Question #2)
I have confirmed with kfong that I can use the charging terminal (unused in the normal use of his Dewalt Interface PCB) to charge the batteries, he recommends I use a 15Amp In-line fuse to prevent high packs draining to low packs, and if I understand correctly, if I am using 16 cell groups, (two 8 cell DC9280 Dewalt packs in series) that I should charge at 59.2v and if I want this done in about 1 hr, I need to do so at 9-10 amps, would a "smart" SLA CC/CV charger for 59.2v (a nominal 48v charger) running at 10 Amps be acceptable to do this?
I know that the Dewalt BMS isn't the best, but I am hoping I can use it and maybe just throw the batteries on the Dewalt charger individually every so often to make sure they are reasonably balanced, say once a month?
Sorry if all these questions are elsewhere, but in all my reading, I only found fragments of the answers, and I just want to be sure before I do something that will damage my A123's.
Thanks!
Question #1)
First off, I have been less than delighted with the Dewalt charger, it works, I guess ... if it HAS too ... Reminds me a lot of the "man's prayer" from Red Green.
I learned from my reading that it's generally accepted that 3.6V per cell of A123 batteries is a solid charge, and since the Dewalt charger isn't very consistant at balancing, short of opening up a pack of 8 (28v DC9280) cells and testing each one, would it be safe to say that if I have a total voltage of approximately 28.8+ on the pack (I can usually get each pack to show at least 29v, some as high as 29.7) by simply "re-charging" again after the first "charge" when all the LED's Stay solid.
It would seem that the charger goes Idle once all 3 lights are solid, so I don't think leaving it in the charger longer makes a bit of difference, UNTIL you take them out again, and put them in again for another 5 mins. or so. Using this method, I have been able to get most of the packs to hit about 27.6-27.9 on the initial charge, and then reach high 28's- low 29's on subsequent 5 min. "top-up charges". Almost all the batteries (I have 8) take 2 top-up charges, but some take 3-4 short top-up charges to reach this level.
Is it safe to say if I have 29v+ on an 8cell A123 pack that they are going to be at or really close to 3.6v?
Question #2)
I have confirmed with kfong that I can use the charging terminal (unused in the normal use of his Dewalt Interface PCB) to charge the batteries, he recommends I use a 15Amp In-line fuse to prevent high packs draining to low packs, and if I understand correctly, if I am using 16 cell groups, (two 8 cell DC9280 Dewalt packs in series) that I should charge at 59.2v and if I want this done in about 1 hr, I need to do so at 9-10 amps, would a "smart" SLA CC/CV charger for 59.2v (a nominal 48v charger) running at 10 Amps be acceptable to do this?
I know that the Dewalt BMS isn't the best, but I am hoping I can use it and maybe just throw the batteries on the Dewalt charger individually every so often to make sure they are reasonably balanced, say once a month?
Sorry if all these questions are elsewhere, but in all my reading, I only found fragments of the answers, and I just want to be sure before I do something that will damage my A123's.
Thanks!