You're pulling about 0.5C. How many amps is the pack rated for?
>>Each time I discharged the battery I ran it until the lights started to dim/turn yellow<<
Don't tell the popular online supplier that you did that as you probably ran the cells lower than 1v/cell and possibly killed a cell or put the pack out of balance
Battery specs are:
Voltage: 14.4V (working) 17.4V ( peak)
5000 mAh min. (72 wh)
4.2 Amp limited by two polyswitch
Battery may be defective
If the battery was operating properly, you should have been able to run longer. I calculate:
32watts/14.4volts = 2.2 amp
5000mAh/2200mA = 2.27 hours
That's under ideal circumstances, but 2 hours should have been obtainable.
You aren't overvolting?
I don't think you did anything wrong by running the pack until the lights dimmed. Past that point is very bad though.
lemme guess - the charger is a blue box about 2x3x7" and you can select the charge current of 0.8 to 1.8 A ?
Got a multi meter ? test the final voltage of the pack... I had a charger which would indicate full charge prematurely (less than 1/2 way) I would have to reset the charger to insure a full pack.
Measure the final voltage of the pack after charging - I think you will be well below the 17.4 peak.
same battery - same problem.
Yep, the charger is the little blue "smart" one. I figured out the under-charge problem just this weekend. When the light turned green I unplugged the charger (from the wall) and plugged it back in. The green/red flash sequence would go and then the charger would start charging again. After a couple cycles like that, it would flash green/red when plugged in and then go to green.
Running one 20w 12v flood and occasional 20w spot, I got tired of urban trail riding after a long day at work before the battery went. It was over two hours as opposed to 1 hour 20 minutes.
Originally Posted by heatstroke
Exactly! That's the charger. I'll test with a multimeter at work tomorrow. Thanks for the advice ....I knew somebody on here would have the same setup!
I was concerned about that, but their site claims that the battery has "One 4.2 Amp polyswitch installed to limit max. discharging current at 8.4 A and to protect wrong polarity". Doesn't that mean I can just run it until it shuts off completely.... let the "polyswitch" do its job? The lights have gotten quite dim with no shut-off occurring.
Originally Posted by paulrad9
Yes, 14.4V pack on a dual beam 12v halogen head.
Originally Posted by Walt Dizzy
Thanks again guys!
I think the polyswitch will not shut off the light except when exceeding the current drain. Just run the lights till they are dim.
My advise is to get a "GOOD" battery charger, something like one the RC folks use and can handle different battery chemistry.
I have the multiplex LN5014, only problem is that I think lifepo4 batteries are on the way and my charger will not handle the new cells.
[QUOTE=heatstroke]I think the polyswitch will not shut off the light except when exceeding the current drain. Just run the lights till they are dim.
Good thinking, a polyswitch is resettable fuse, it's used to protect against over current faults.
To protect the pack from over discharging you need a protection circuit.