Ex-Goose Battery conversion

Power wheelchair board for REAL info!

POWERCHAIR MENU! www.wheelchairdriver.com/powerchair-stuff.htm

Re: Ex-Goose Battery conversion

Postby ex-Gooserider » 12 Jan 2018, 07:11

remaining graph files

cell-grph-37-43.zip
normal .zip file, open graphs w/ PL8 S/W
(293.63 KiB) Downloaded 153 times

cell-grph-44-54.zip
normal .zip file, open graphs w/ PL8 S/W
(344.57 KiB) Downloaded 153 times

cell-grph-55-56.zip
normal .zip file, open graphs w/ PL8 S/W
(102.61 KiB) Downloaded 151 times


ex-Gooserider
T-5, ASIA-B
Jazzy 1100
Jazzy Select 6
Quickie Q-7
Invacare Mariner
Want to make / get a better chair, ideally one that stands.
User avatar
ex-Gooserider
 
Posts: 5962
Joined: 15 Feb 2011, 06:17
Location: Billerica, MA. USA

Re: Ex-Goose Battery conversion

Postby Burgerman » 12 Jan 2018, 09:57

What concerns me is that while most of the cells charged in less than 30 minutes, and gave a fairly narrow range of mAh return values, I had several that didn't stop until the "safety time-out' hit at the 4 hour mark. These had much higher values when they terminated... How do I treat these when figuring out the cells for each parallel string?

I didn't look at every graph, but spot checking the 'pack capacity vs time' screen, which seems to me like the best equivalent of mAh returned over time, it looked like the 4-hour cells all had similar curves where the mAh went up really fast for the first 20-30 minutes, and then switched to a slow but steady increase at around 1mAh every 10 minutes or so...

I'm wondering if it would be better if instead of using the mAh returned when the cells cut off at 4 hours, I used a number from just after that knee in the capacity curve - say around 25 minutes????


I dont see any option. I never saw that happen other than once or twice and still dont know why. I discharged the cells by a fair bit, recharged and they ended normally.
User avatar
Burgerman
Site Admin
 
Posts: 65050
Joined: 27 May 2008, 21:24
Location: United Kingdom

Re: Ex-Goose Battery conversion

Postby ex-Gooserider » 12 Jan 2018, 21:21

Thanks...

I really don't want to repeat this exercise of waiting for the cells to self discharge and recharging the bunch - I want to get the pack built...

The problem with doing the discharge and recharge, is that if I only do it to some of the cells, they won't be starting from the same point as the others... At least if I pick numbers off the graphs for the 4-hr cells, then they all started from the same state...

As a thought, would it make any sense to reduce the safety time out on the single cell preset to something like one or two hours instead of four?

ex-Gooserider
T-5, ASIA-B
Jazzy 1100
Jazzy Select 6
Quickie Q-7
Invacare Mariner
Want to make / get a better chair, ideally one that stands.
User avatar
ex-Gooserider
 
Posts: 5962
Joined: 15 Feb 2011, 06:17
Location: Billerica, MA. USA

Re: Ex-Goose Battery conversion

Postby Burgerman » 12 Jan 2018, 21:25

2 hours should be plenty on one cell. Its only longer because if multi cell it may need time at CV to balance.

Increase the 20mA to 25 or 30mA on single cell charging. May be a better way. As long as all the same though.
User avatar
Burgerman
Site Admin
 
Posts: 65050
Joined: 27 May 2008, 21:24
Location: United Kingdom

Re: Ex-Goose Battery conversion

Postby ex-Gooserider » 14 Jan 2018, 07:17

OK, will make those changes to the preset, which will help on the next pack at least... (presumably make the changes when doing a single cell preset for other folks?)

I am just hoping to avoid having to do the process over on THIS pack... That is why I'm wondering about doing the thing I suggested previously about trying to get an estimated reading from the graphs on the 4-hour cells - that would save the weeks of time to redo the whole cycle from the start...

ex-Gooserider
T-5, ASIA-B
Jazzy 1100
Jazzy Select 6
Quickie Q-7
Invacare Mariner
Want to make / get a better chair, ideally one that stands.
User avatar
ex-Gooserider
 
Posts: 5962
Joined: 15 Feb 2011, 06:17
Location: Billerica, MA. USA

Previous

Return to Everything Powerchair

Who is online

Users browsing this forum: iainsherriff, tettralytic and 32 guests

 

  eXTReMe Tracker