Friday, September 11, 2009

Yea! Pictures!


Da car, nestled into it's "Motorcycle Parking" spot at work. You can't see it but the charging outlet is on the post behind the car. Thanks again to my workplace for providing the charging facilities.

So, the warrantied DEKA 'Intimidator' battery was delivered about ten days ago (just over two months after the first one failed) and I stuffed it in to replace battery#5 that was failing pretty rapidly. I discharged and recharged 'cycling' the new battery several times to get it broken in. Yes you do have to do that, tossing a new horse into the team and running them hard can cause stumbling and crashing problems...
I pulled off all the Volt Blocher boards before swapping in the battery and did a little testing and tweaking and then remounted them in a more managable arrangement. I got a few resistors swapped around and now all the boards operate within about a tenth of a volt of each other. I put the boards that operate a little low on the batteries that operate a little low, makes everybody happier.

"What, the batteries aren't balanced? Heresy!! "
There are batteries of three different ages and two different manufacturers in the pack. Of COURSE they aren't 'balanced' Don't be silly.
In fact I think the battery balancer that was on the pack (until it was recalled by the manufacturer) was part of the reason for some of my battery failures. Even when 'new' both the original and replacement DEKA batteries seem to run 2-3 tenth's of a volt lower than the HAZE units (which have a couple tenths of variation between themselves) and having something that's trying to bring them all to the same voltage seems to cause the units that run naturally lower to overcharge just enough to vent a bit. The venting causes a reduction in capacity, which increases the tendency to overcharge, and vent, and 20-30 cycles later you have a failing battery.
The traditional fix for this problem is to throw money at it. Just replace the whole pack. Then they'll be balanced...if you're lucky. Being cheap, I don't much like the $1500 solution.
My fix is to have the Voltage/Overcharge limiting boards set so they match the battery they're attached to. The 0.3V difference between the switch settings on this version of the VoltBlocher boards turns out to be just about right. (Brian, take note!)
As a result, when it's nearing the end of the 'bulk charge' part of the charging cycle with the pack sitting at around 60deg.F I'll see voltages of 14.7, 14.3, 14.5, 14.5, 14.3, 14.5, 14.5
#2 is a two year old HAZE and #5 is the new DEKA. If I take the boards off, some of the voltages will shoot up to 15.0 or 15.2 wich will kill them in short order.
I'm not sure what the deal is with #1, it always runs a bit high, though part of that is maybe measurement error. Anyway, we're now at 2000 miles...and with only four (total) battery failures...Huzzah!!

1 comment:

  1. Still think you need a herd of hamsters to run that thing. Probably be less expensive than those darn batteries! Can't you just hear the squeaky wheel turning in the back?

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