Next battery build for 100 amp continuous 200 amp peak.

[litespeed]

So I have a 14KW MaxE/QS 205 3.5T 17" Vector framed monster which I love. I ran it this year off of a 20s15p Koinion pack I built and it did great except when riding it as hard as I like. I am peaking at 196 amps and get big voltage sag after 20 to 30 seconds on a fresh charge. After 30 mins into a ride I hit low volt easily with a lot of throttle. So a couple questions come to mind.

1) Would it make sense to go to 22s to lower my total current? I have read more times than not that 20s is the sweet spot for the MaxE but thought I would check to make sure things haven't changed.

2) would a 20s12p or 22s12p 30Q or go to Multistar 20s or 22s 32 amp pack made up of 16000 packs?

I'm sure long term the 30Q would last longer but they will cost about $200 more at today's rates on the Multistar batteries but I could then swap to new technology batteries sooner since I would assume that the multistars would only be good for 300 or cycles. Weight would be about the same or possibly the 30Q would be slightly less with slightly more amperage....36 vs 32 amp. I have thoughts of going to a QS 273 in an 18" wheel ( to do a 1 cross and a 3.5 wide tire ) one day so would like what ever battery I go with to work with this as well. That would mean 150 amp continuous and 250 amp peak.

Thoughts?

Tom

 

[Ohbse]

I'm running the same motor/wheel combo and just replaced my battery with 20s12p of 30q cells, works great!

Total pack IR is about 30mOhm, or put another way with 200 amp discharge it will sag 6v.

20s is definitely still the sweet spot for Max-E, when pushed to the max 22s will not help you, especially not with a fast wind where RPM is not a concern.

 

[litespeed]

That's what I wanted to hear....

30Q +1
Multistar 0

Tom

 

[atarijedi]

I'm working on a build using a Qulbix frame, I think I'm gonna go the multistar route since I don't feel like building a huge pack.

 

[Quokka]

Tom, I would also look into the sony vtc6 cell. I think it has a bit more grunt than the 30Qs. Some tests are rating it fot 19 amp cont and up to 30 amp bursts. I believe that you should build a battery that can deliver 50% more than you plan to use so you dont reduce the cells life prematurely due to high discharge rates. The 30qs are still an outstanding choice though and are getting cheaper
I too am building something that can power the 273 with 18650's. I will go 22s with the adaptto and cut the hv to 90v. 4.1 v per cell- i know you miss out on the other .1v but when you look at the performance curves there's not a lot of stored energy in that section and by not charging fully you further help your packs lifespan. Its also worth thinking about how you move all those amps through your series connections without them getting to hot. Check out alexs latest post in the vector section with his monster battery. He has some skills that guy
Btw- sweet bike

 

[litespeed]

My understanding is that when you go 22s it will lower the amperage down to below the 14 KW you can get at 84v or 20s. VTC6 was on my list until I saw the pricing. The 30Q are $2.97, VTC5's can be had for $3.61 and 25R are $2.43 compared to $5.34 each for VTC6'S.

It actually looks like Multistars would be the easiest and most powerful but a custom 18650 pack of VTC6'S would be best long term.

Price wise I'm looking at,
$1100 plus shipping on a VTC6 20s10p 300 amp peak pack. 31.20 amp pack
$875 plus shipping on a VTC5. 20S12P. 360 amp peak pack. 31.20 amp pack
$600 plus shipping on a 25R. 20s12p. 240 amp peak pack. 30 amp pack
$840 plus shipping on a 30Q. 20s14p 210 amp peak pack 42 amp pack
$500 to 700 plus shipping for a 20s2p 320 amp peak pack for multistars depending on the sale at the time. 32 amp pack

All of the 18650 packs have to be built and the added cost of nickel, wire and copper pieces to build the pack. I want to build my own but wonder if the multistars make the most sense?

Tom

 

[Quokka]

If you do go down the 18650 route make sure you can get access to a good spot welder. That was the hardest part of my last battery build... had to build my own.
I thought that if unlocked, the new maxe software could pump out 200 battery amps at 90v? 18kw? I better sort that outbedore i get hot glueing

 

[ecycler]

I have a 20s10p battery build with VTC4's and a 21s9p pack with 25R's. The VTC's hands down outperform the 25r's, especially in cold weather.

 

[litespeed]

I'm set on the spot welder. I have a 800 watt second capacitor discharge welder I built from an online set of boards-instructions. Probably one of the most powerful and versatile welders on this board.....haven't figured out how to weld copper or brass though but it wasn't for lack of trying. The unlocked both entices and scares me at the same time. I would love a bit more raw instantaneous power at lower speeds.

My pack of VTC3's is still plenty powerful but just can't keep up on long ride at high amp discharge. VTC5's hands down beats all other 18650 out there on paper for watt per $$$ and discharge with a very small weight penalty of exactly 20 cells to match the VTC6 capacity.

Tom