mc_burn

I just bought a Niterider Classic Select halogen light. Should I run the battery so it is completely discharged the first time I use it or is it okay to charge it after each use? The owner's manual does not specify.

thanks

paulrad9

Then don't do it. I had (actually still have) that light and must have bought it 12 years ago and it's still going. Sometimes it sits half charged for a year; sometimes it gets charged only after on night's ride; other times I ran it down to empty without noticing.
So, don't worry about the light. Discharging fully does more harm then good. Just use it as it was intended, charge it when it gets near empty and have fun.

bfromcolo

I believe I have the same light. Performance bike version with 10/15W halogen bulbs. My owner's manual says to discharge and then charge it for 9 hours. If you go this route discharge with a fan on the lights or they will over heat.

It's a NiMH battery pack, so technically it is not necessary to discharge, but how will you know how long to charge with the dumb slow charger if you don't. If you have a volt meter you could take readings periodically while it's charging and stop when the pack is charged, you may want to go through the discharge/charge cycle to determine what voltage you are looking for. Probably in the 7.25+ volt range if the pack is made up of 5 NiMH nominal 1.2V cells.

Edit: The manual defines discharged as when the lights start to noticeably dim, NOT when they are dead. FULLY discharging NiMH cells is bad for them and will reduce their life.

dekindy

https://batteryuniversity.com/index.htm

This site is an authority on batteries. It is fairly easy reading. I learned a lot and refer to it often.

MR99SI

No not all the way down!

cyccommute 

"All the way down" for Ni chemistry batteries is 1 V per cell. If you are going to discharge the battery...something that 'should' be done occasionally...you need to do it in a controlled manner. If you can't control the final voltage, it's best to just not do it. You could do more damage to the pack then you would by not doing periodic discharge.

There are some chargers out there that will discharge to the set voltage for you. They are not cheap but they do a better job of charging your batteries then the OEM charger does anyway. My favorite is the Maha C777plusII


Not only will it discharge properly (any battery, not just your light batteries), but it will charge properly too. The charging regime for NiMH battery packs should be controlled for voltage and cell temperature. If you overheat an NiMH battery, you can end up shortening the life of the battery significantly.

The above only holds for Ni chemistry batteries. Li and Pb batteries should be treated entirely differently. For that discussion go over to Battery University as dekindy suggests...you should do that anyway

froze

These newer batteries do not have the memory effect anymore like the old NiCad batteries did, thus you do not need to completely discharge or even fully recharge the battery like the old ones. It is recommended that for the first 4 cycles that you fully discharge and recharge new batteries, after that a full discharge and recharge is only needed to be done once every 2 to 3 weeks if used every day. The biggest damage to NiCad's comes from overcharging thus a smart charger is the safest way to go.

The new Li-Ion is completely free of memory issues thus with these you don't need to fully discharge or even fully recharge-ever.

cyccommute 

We've had this discussion before. All Ni chemistry batteries will grow crystallites which are what results in memory. NiMH does it less than NiCd but it still does it...it's a physical phenomena of the Ni matrix. Periodic cycling of the battery will extend life of the pack but you don't need to do it as much.

I didn't want to muddy the waters with the Li-ion batteries since it's not likely that mc_burn has one of those.