Battery advice

[Mayqswet]

I found a forgotten Specialized bike light in my garage yesterday. It still works fine and seems to use a 12 or 15W halogen bulb. My dilemma is that the battery pack is rather large and heavy, requiring five D-cells.

What's the most economical way to supply the power it needs without all the weight? I'd like to find a smaller rechargable pack that can be tucked neatly under the top tube or a water bottle cage.


Mayqswet

 

[Zero_Enigma]

Hmm.. you could try with 5 x C or 5 x AA batteries.

AA's would probably be the cheapest but the least runtime given the lower mA rating. However it would be lighter for sure. I just cleared out 10 x D cells which are dead here so yah I know the weight of 5 x D is not really fun.

 

[Mayqswet]

Thanks for the ultra-quick response.

Now for a couple noobie questions:

Would it be correct to assume that all I have to do is match the 7.5 volts that the 5 D cells supply? If so, what is the best way to fashion the 5 AA batteries together to achieve that?

Also, I took it apart and discovered that it uses a "NR-10" bulb/reflector. Could I simply take that one out and swap it with a 15 or 20W replacement?

Mayqswet

 

[HEY HEY ITS HENDO]

HEY Mayqswet, ok forget the AA battery pack idea, there is no way it could supply enough current or voltage..... or even runtime
by far the easiest solution is to get a 7.2v/ 6 x sub c RC battery pack like this one..... HERE
........ and stick to good quality brand, you will save money in the long term through reliability and capacity

also yes you can increase the wattage easy, but only if you have metal lamp housings ..... plastic housings may melt with the extra heat generated