Saturday, December 31, 2016

New Years: Review and Distraction Reduction

2016 was certainly an interesting, and in some ways unexpected year (though if you didn't think Trump had a chance, you should get out more).  It being the end of the year, it's time engage in the traditional American process of New Year's Resolutions - generally followed by the traditional American process of forgetting about them by February, or March at the latest.

Last year, I set a New Year's Resolution related to this blog.  I resolved to post something - no specific requirements, just something - every week.

Has this resolution been successful?  Yes, it has!  I posted every Saturday evening in 2016, with the exception of one post that got published Sunday (the SolPad post) because it was time-sensitive and not ready Saturday night - I started it on about Thursday, and it was a long one to write.

Coming into 2017, it's time to consider something else to add to my life.  I want this to be something that will both improve my life, and improve me as a person.

I've decided what it is: Radical reduction of distraction.

What?  Why?  How?  Read on!

Saturday, December 24, 2016

BionX 350 HT RR L Rebuild to 13.5Ah

If you recall properly from last week, I tore apart a BionX 350 HT RR L battery.  This being my blog, it probably means I'll rebuild it to a larger capacity - and you're right!

I left off last week with an unfolded pack and a bit of data about the cell layout.  This week?  Time to build the same thing!

This is, by far, the most complex pack build I've done.  Read on for the details!

Saturday, December 17, 2016

BionX 350 HT RR L Teardown

Another new pack to tear down!  There are so many fun variants of the BionX packs over the years!

Today, I've got a "BionX 350 HT RR L" pack.  Quite the name, and I'm sure the name means something to someone who has decoded all the BionX naming conventions.

But, to me, it means a new battery layout to investigate and, perhaps, rebuild - and that's very exciting!

Last week, I pulled apart a newer BionX 48V pack, discovered that the design is incredibly modular, easy to repair, and noted that such features are useless when BionX won't sell you parts.

This is the new pack for this week.  It's a rear rack mounted pack, and it's quite massive compared to the Trek Valencia Ride+ pack, which is the other rear rack pack I've worked with (Teardown 1/2, Teardown 2/2, Rebuild).

This pack comes rated as a 37V, 9.6Ah pack - so inside is almost certainly a 60 cell layout, but the standard downtube layout won't fit in this pack. 

What's in it?  I assure you, it's 60 cells - so read on to dive in with me!

Saturday, December 10, 2016

BionX 48V 8.8Ah SL 350 HT XL Pack Teardown

I'm kind of a weird person.  I get really, really excited when I get new battery packs in to pull apart.

And I've got a new pack to tear apart!  Today, I'm disassembling a shiny new-to-me 48V BionX 8.8Ah pack!  What's inside?  I have no idea, but I'm really excited to find out!

This is the SL 350 HT XL pack - 8.8Ah of fury.  This isn't the biggest pack BionX sells - they've got a 11.6Ah 48V pack on the market now, but this is a much more recent pack than most of the ones I see.

Sadly, this is a "warranty bricked" pack.  If BionX is replacing a pack under warranty, they just brick the newer packs remotely and ship out a replacement.  I get that lithium battery shipping is complicated, but I'm especially annoyed about this policy after pulling the pack apart - and you'll see why shortly.

So, read on as I dive into this reasonably modern ebike battery!

Saturday, December 3, 2016

A Tale of 3 BionX Packs: Self Balancing LiMn

I've worked with a lot of BionX battery packs over the past two years - stuff I've torn apart, stuff I've rebuilt.  The older packs are an interesting series of packs all built around the Sony US18650V 1600mAh LiMn cells, and these older packs stand out, in a way, by what they don't have.

They don't have a balancing BMS or any balance leads!  Instead, they have cells that, at least on paper, claim to be self balancing.

How well does it work in practice?  Perhaps surprisingly, very well!

I have a selection of live packs to play with (old and worn out but still holding a charge) - read on and let's find out how well some old BionX packs are balanced!