Ok, finally getting the battery done, so may as well start up my build thread. This thread will be a bit slow as I wish to take it easy because this is my first DIY attempt.
Parts I will be using (enough to at least see if everything is in working order)
• Alienware VTC3 trigger remote • 2 Trampa VESC 6.0 • Torqueboard 218mm trucks • Torqueboard V4 mounts and clamp • Powell Peralta - Kevin Reimer Samurai Skateboard Deck • 60 Samsung 30Q’s in 12s5p configuration • Ollinboards antispark/switch/fuse • Servo Y split • 83mm Evolve wheels • 97mm Abec 11 75a wheels • Trampa 33t wheel pulleys • 2 Maytech 6355 sensored motors • 6s-14s Cycle satiator charger
Parts still to get
• Battery/vesc enclosure • T-90 connecters • 10 or 12 AWG silicone wires • Heat shrink wraps • 18 AWG or thereabouts for balance lead • Maybe some more pure nickel strips
I was not sure which way to go for batteries, Li-po or Li-ion, but decided to go Li-ion first and see how it goes. If the sag is not reduced enough to an acceptable level, the enclosure screw spacing is large enough to go for Li-po if I wish to in the future. Also Li-ion is thinner.
After doing some online research about LI-po, I learned that 60c,75c,90c etc is bogus. There is no law to stop companies from slapping fake “c” ratings on the side of their products.
For example, the 2s2p 7200mah 90c battery from SMC should produce an Amax of 324, which is not the case at all. It would only be able to achieve a “c” rating of just 36.6! That means it can only do continuous Amax discharge of 131 amps.
To SMC’s credit, they are one of the very few to be honest with their products. I cannot find their page explaining why they put 131Amps on their product page but it is there somewhere.
The true Amax at “c” is 131amps. The advertised 90 “c” is just in comparison with what other companies put on their products.
No wonder a lot of people complain about puffing because they thought the “c” was what the product was, which is not.
Li-po still have better Amax discharge than Li-ion by a large margin, but no where near the advertised “c”.
Here is the calculations of my 12s5p 30Q battery pack. Max motor amps will be limited to 30amps for a combined Amax of 60. I worked out the “c” of a 30Q which is just a mere 5!
I had someone else make the battery pack for me and I will do all the rest myself. Below is the image of the pack that will power my board. I have not picked it up yet, but did request a photo taken so I have an idea of what work he did on it.
I’m somewhat concerned about the cuts and what appears to be mild burn marks on the batteries. I’m sure it is just superficial but if any of you think it is not, please say so. I will have to do the soldering of the tabs myself
That pack in the photo is actually four separate parts. A pair of 2p on both sides and a pair of 3p in the middle. I think I will be using nickel strips and solder them to the tabs at the end. Also solder 10AWG wires black and red on the other end. Would that be ok or do I also have to make sure that each series is also connected in parallel instead of just the two ends?
I will update this thread tomorrow afternoon with pics of all the other parts I will be using. Just really need to talk about the battery as I’m not fully confident that I know what I’m doing.