15C Zippy Flightmax Batteries Gone?

[betarambo]

I have a pile of these batteries for my kid's electric motorcycle (Oset). I decided to order another set but can't find them. I see 20C and 30C equivalents for decent prices but they are not the same size or weight as the old 15C. For the 6s1P packs I use I see:

15C 20C 30C
weight 681 754 784
length 152 145 146
height 50 52 53
width 45 50 53

I tend to wonder if these specs are real. I am guessing that the dimensional differences are likely to be more about measurement uncertainty and how puffy a pack was when it was measured, but it appears that the weight trend is real. This could be from thicker wires if nothing else.

My main concern is the width of the batteries, but all the dimensions concern me. I designed a tight cover/box for these batteries and I have found that I have a hard time with 20C Turnigy equivalents because they are slightly wider. I made it to hold 4 of these batteries side by side and I can just barely sub in two Turnigies, but I definitely cannot fit 4 of those.

So this leaves me with two questions for you gods of electrons, pedaling, and general geekery:

1. Are the 15c variants truly gone?
2. Does it make sense that a higher C rating means more weight and maybe a little more physical size?

For reference I mount 4 batteries side by side with the discharge wires up, all on the same end like this:
IIII
Where an I is a zippy. I can just barely get away with two Turnigy 20c packs instead like this
IIii
Where i is the Turnigy. I cannot fit all 4 of them being Turngiy like:
iiii
as the width is too much.

Thanks in advance for the wisdom and also for the clever remarks about my super lame diagrams.

 

[neptronix]

I bought the 15C.
The secret to their weight loss is partially that they are low on capacity.
I measured around 4.7ah on mine which were brand new.

 

[dogman dan]

It's getting hard to find anything in stock at the moment, let alone a particular c rate or brand.

How hard is it to build a new box? Long term, your only solution is to build for the larger turnigy cells, then shim if you happen to be using the smaller kind.

 

[Kingfish]

All of mine are 5S 5Ah 15/2C. In the three years, there was one small subtle upgrade from 12-AWG battery wires to 10, the physical size shrunk about 1mm in width, and they seemed to me to be more puff-resistant (or perhaps I just got better at management).

Been lurking on HK for replacements. They've not been available for some time now, at least since the new year. Best I can do is upgrade to 20C which is slightly dimensionally different, but not an impediment to my bags. I think adding 20C to my stack might put them in slightly more stress being faster at charge/discharge - graybeards will know more than I.

I only need 7 to restore my 2011 road trip quota.
LiPo Daddy, KF

 

[dogman dan]

I'm starting to wonder if HK is still in the battery business. Seems like nothing has been restocked in months.

 

[triggeraa]

Was waiting for USA store to re-stock 5 & 6S 20Cs for months. Could not wait any longer and purchase 19 pcs of the 3S. This week a few of the 5S 20C were available and picked up 6. They seem to be suffering and extreme manufacturing shortage. Lots of profit going out the window due to lost sales.

 

[betarambo]

I ended up going with some 8 aH 6s Zippy's in 30c. The cost was actually pretty close per WH to the old 15C. The 8 AH works out perfectly as I need about 50% more capacity anyway. These ones are a bit longer and a lot taller. I modified my box to fit both new and old. I bought 4 of them (out of stock now) and they all showed up fast (from the USA warehouse) and had no issues. Being 30C and 8 aH they had to use a bigger connector (5.5mm) so I had to revert to soldering to get back to my normal connectors.

Everything looks good. I think these will be my new standard assuming this weekend's test works out.