View Single Post
Old 07-25-2011, 09:45 AM   #9 (permalink)
MetroMPG
Batman Junior
 
MetroMPG's Avatar
 
Join Date: Nov 2007
Location: 1000 Islands, Ontario, Canada
Posts: 21,058

Blackfly - '98 Geo Metro
Team Metro
Last 3: 70.09 mpg (US)

MPGiata - '90 Mazda Miata
90 day: 54.01 mpg (US)

Winter beater Metro - '00 Chevrolet Metro
90 day: 73.57 mpg (US)
Thanks: 2,843
Thanked 5,704 Times in 2,948 Posts
Battery pack woes!

So, four years of light use later, the battery pack in this bike has given up the ghost.

Power output from the motor is low, and the "fuel gauge" LED's on the twist throttle show "empty" under anything but the lightest amount of assist. Also, the charger will show "green" (charged) indicator almost immediately after plugging it in, which isn't normal.

As mentioned in post #3, the 24 volt battery pack is comprised of 2x 12v 12AH (@20H) valve regulated sealed lead acid batteries wired in series. They're the type of battery you'd see as backup in an alarm system, for example:



(The two batteries on the left are the same type of 12 Amp hour ones used in the bike's battery pack. The three on the right are 7 Ah.)

One of the pair is dead. The other still has about 2/3 of its rated capacity, after doing a simple capacity test using a 12v DC/AC inverter.
Attached Thumbnails
Click image for larger version

Name:	batteries-7ah-12ah.jpg
Views:	224
Size:	97.0 KB
ID:	9066  
__________________
Latest mods test: 15 mods = 15% MPG improvement: A-B test, 2007 Honda Civic 1.8L, 5-speed
Ecodriving test:
Manual vs. automatic transmission MPG showdown: Nissan Micra 1.6L



EcoModder
has launched a forum for the efficient new Mitsubishi Mirage
www.MetroMPG.com - fuel efficiency info for Geo Metro owners
www.ForkenSwift.com - electric car conversion on a beer budget
  Reply With Quote