I have been building various custom batteries friends and family. I have some cells on order from nkon.nl and was wondering if their’s a demand for a cheap 10s4p pack with sony vtc5 cells (2600mah 30a), the price would be between $275 and $300 for the complete pack including a charge only BMS. Let me know what you think about the price. I am willing to build custom packs with your choice of cell. Is there a market for this sort of thing? the entire process will be documented so you can thoroughly see the quality put into these packs. ETA on when they would be ready is unknown atm, but hopefully within the next 2-3 months at most
I figured it was worth asking. their is no point making custom packs if no one is going to buy them.
I don’t know the answer to your question but I imagine if you look at what other vendors are selling and can sell something that is on par or better quality wise and/or at a better price with the same/similar level of support then it’s probably worth starting and advertising more to see how much demand there is overall instead of just from people here (many of which probably make their own batteries too).
The price is very similar in the end. The cells are 2600mah instead of 3000, but are. Capable of 30a discharge with almost no voltage sag. A 10s4p 30q pack can do 80a at best where a vtc5 pack could do 120a. The range lost for the discharge increase is well worth it imo. The range might not actually be affected much either, a 30q pulling 20a is no where near 3000mah in the end.
I forgot to mention that my low prices are sheerly to attract more potential buyers. They may go up slightly in the future. I think its crazy to charge so much for a battery. I guess i am taking a page put of @Boardnamics book lol. Cheap prices and a little extra effort means alot more potential profit
Honestly, there are a lot of people who don’t want to build there own battery or just don’t want to spend the money for the right equipment to make one, two batteries. Well build batteries are always on demand.
But, the focus should be on well build packs. How you plan to build this packs? There are a lot of ways to build one, but there also many ways to build crap. Will it be pcb based? Level cell fusing? Flexible packs or just a stiff pack welder together with some nickel? Where you get your nickle from? As well from nkon? If no, did you and will you test every order if it’s pure nickel?
Do you have some pictures you could provide us from packs you already made?
Hope that all sound not arrogant just so much things I think which should be clear for people who want to buy your packs.
I completely understand. No one wants to buy crap. The packs are built with or without the black cell holders and fused together with 10x 0.2mm nickel from nkon because its obviously genuine. The ampacity is relatively low, so i use braided copper cable to bridge the points that need extra current transmitting abilities. I can build the packs and glue the cells together, but it seems to work better to wrap each p group in fiberglass reinforced tape, and then wrap them all together. This gives it just enough flex for something like a vanguard deck. I was dumb ans never got pictures of my old packs… oops. But it seems that if i post pics of finished products and the build process later, their should still be interest? And no, you dont sound arrogant. I appreciate your feedback. Alot more questions will be answered when production starts. I think i am going to continue with the idea and start building.
I have used both cells in a 12s6p pack on 2 identical boards. The vtc5 cells are capable of the 30a rating where the vtc5a sag heavily at 35a, and lose significantly more capacity at 30a than the vtc5. after noticing this i took a few spare cells and did a torture test. the actual capacity of vtc5a cells is lower than stated. the vtc5 cells managed to stay within 100mah of there rating if discharged at 20a. i was surprised at the results because at the time i payed nearly $1 extra per vtc5a. I cant remember where, but somewhere on he forums, someone did a lifecycle analysis of the vtc series cells. and the 5/5a averaged nearly identical lifespans. I don’t remember what amperage they tested though.
I do have data to back up my claims. all the data seems accurate, alot of people on the forum use this database
Should i add a charge port on the batteries? it seems some people use odd charger connectors. I will at least include charge port wires ready to be soldered to your own port. the same issue goes for fuses, most people charge 10s at 2a, but ive seen a considerable number who use 4a+. i guess i could add a fuse fuse holder and have the fuse be customizable for several values
The VTC5A are not a 35A cell, it´s a 25A cell according to the testing from mooch.
I just had a short look on the side you linked.
Idk, but if I see that graph, I would say the VTC5 sag way more at 30A than the VTC5A. Besides this, the VTC5 get up to 80 degree if discharging the cell with 20A over the full charge cycle while the VTC5A stays at 45degree.
But that´s just from what I can read. I don´t have any real life experience like you with this cells.
The vtc5a is a good cell for sure, but the thermal issue is much more prominent than the testing shows. Also, the site owner says that the asterisk next to a cell name means that it was testes in a parralel block so its high current rating is not completely accurate. I missed it when i was first comparing cells a long time ago and it really threw me off. Both cells are great, but the vtc5 is realistic in its claims and thermally, has done great for me. Even when enclosed. Another perk is of course the fact that you will never draw 30a from it constant. Even on a 6384 dual motor hill climb board 12s6p, it uses 75a or so for the toughest terrain. Ive only pulled that current for a few seconds before i had finished. For that reason, a genuine 30a cell really did a fantastic job. Analytics showed almost no voltage sag! If you have any other concerns or questions, i would love to talk about them.
I stated previously that i was dumb and never took pictures. I never had the need to remember them, they were for friends or family. Theres a slim chance a friend will be needing one built from some samsung cells soon. Maybe i can document it then. Ill talk to him and see.