Cycling and bicycle discussion forums. 
   Click here to join our community Log in to access your Control Panel  


Go Back   > >

Electronics, Lighting, & Gadgets HRM, GPS, MP3, HID. Whether it's got an acronym or not, here's where you'll find discussions on all sorts of tools, toys and gadgets.

User Tag List

Reply
 
Thread Tools Search this Thread
Old 03-13-09, 04:33 AM   #1
daven1986
Senior Member
Thread Starter
 
Join Date: Feb 2008
Location: UK
Bikes:
Posts: 2,324
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Which batteries?

Hi,

I put some fully charged 2500mah uniross batteries in my fenix torch and after one 30 min run on full beam they are dead. Is this run time normal and if not what batteries should I use?

I am also about to fit a horn (6V 1.5A) and would the same happen with this batteries - again which ones should I use?

Thanks

Daven
daven1986 is offline   Reply With Quote
Old 03-13-09, 05:20 AM   #2
Unknown Cyclist
Senior Member
 
Join Date: Jul 2008
Location: UK
Bikes:
Posts: 1,757
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
If the 2500mAh batteries are AA NIMH then you'll need 5 of them to power your horn and they should run it for about 1hr 40 mins.

I don't know what the runtime on your torch should be, but you said batteries and judging by the capacity I guess it's 2 x AA NIMH.

If it is try changing the batteries, if one of the batteries is a bit tired it will effect the overall result.

If the batteries are a bit elderly, some new ones might perform a lot better.

Finally, if all your batteries seem to be underperforming, suspect your charger.

Unknown Cyclist is offline   Reply With Quote
Old 03-13-09, 05:23 AM   #3
daven1986
Senior Member
Thread Starter
 
Join Date: Feb 2008
Location: UK
Bikes:
Posts: 2,324
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
they are NIMH. for the horn I was going to put 6 in.

might try charging them again. Is there a way to see how much charge is left in a battery?

Thanks
daven1986 is offline   Reply With Quote
Old 03-13-09, 05:45 AM   #4
Unknown Cyclist
Senior Member
 
Join Date: Jul 2008
Location: UK
Bikes:
Posts: 1,757
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Measuring the voltage with a voltmeter or multimeter should give you a rough idea.

IIRC cell voltage shouldn't go below 1v for NIMH fully discharged and should probably be somewhere ITRO 1.4V when fully charged, depending on cell make, condition and type/quality of charger.

This isn't the same as measuring the voltage under load, a healthy looking cell can sag when under load.

Hope this is of some help....

Unknown Cyclist is offline   Reply With Quote
Old 03-13-09, 06:13 AM   #5
kf5nd
Senior Member
 
kf5nd's Avatar
 
Join Date: Aug 2004
Location: Houston, TX 77095
Bikes: Specialized Sequoia Elite, Schwinn Frontier FS MTB, Centurion LeMans (1986)
Posts: 1,470
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
you might have ONE that has gone soft on you. Check with voltmeter after the group of them has apparently gone dead. You might find that most of the are good, but one is near 0 volts
kf5nd is offline   Reply With Quote
Old 03-13-09, 06:33 AM   #6
bhkyte
Senior Member
 
bhkyte's Avatar
 
Join Date: Sep 2008
Location: York UK
Bikes: 2X dualdrive Mezzo folder,plus others
Posts: 2,832
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 25 Post(s)
You could try fully discharging them and recharging them several times. This is suppose to be less usefull for NIMH batteries rather than older NICAD, but I have had good results occasionally with this. I dont think this is the problem as usually this occures if the batteries have not been used for a while, but it might be worth a try.

good luck
bhkyte is offline   Reply With Quote
Old 03-13-09, 07:04 AM   #7
daven1986
Senior Member
Thread Starter
 
Join Date: Feb 2008
Location: UK
Bikes:
Posts: 2,324
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
thanks all, I don't think I have used them for a while so perhaps the charge / discharge could work.
daven1986 is offline   Reply With Quote
Old 03-13-09, 07:39 AM   #8
2_i 
Senior Member
 
Join Date: Sep 2005
Location: Michigan
Bikes: Trek 730, Bike Friday NWT, Brompton M6R*2, Trek 830, Trek 720, Dahon HAT060, Dahon HT060,...
Posts: 1,558
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 7 Post(s)
You can learn a bit about battery performance by going to the sites of major manufacturers, such as:

Panasonic

from where you can download general articles on the batteries and exemplary specific data sheets. The batteries lose their capacity over their lifetime and capacities for marginal manufacturers are often inflated. Battery capacity usually drops with an increase in the discharge current.

When combining individual cells, it is advisable to use identical cells from the same manufacturer. As my consumption of rechargeable and some specialized cells is high, I lower my costs by periodically ordering batteries in large quantity over the internet.
2_i is offline   Reply With Quote
Old 03-13-09, 08:33 AM   #9
Unknown Cyclist
Senior Member
 
Join Date: Jul 2008
Location: UK
Bikes:
Posts: 1,757
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Battery University
Unknown Cyclist is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -6. The time now is 01:00 PM.