Cygolite DualCross 300 battery specs

[4thpage]

Hi, all! I'm just getting into the game here, and have an old-model DualCross 300 (not the PRO version). I'm thinking of scratch building myself a light, but would really like to use the battery pack from the DC 300, because it is a pretty slick package.

2 questions:

1. Does anyone know the specs (total V, I, etc.) on the NiMH battery pack the DC 300 (not PRO version) uses? Do the output specs on the charger give any indication as to the output on the battery?

2. If this is too weak to power some of the newer high-brightness LEDs out there, any suggestions as to other slick battery packs/chargers and where to buy them? I'm not up to building my own batter pack at this time.

Thanks for helping the newbie lovecpf.

 

[Christexan]

Lost my quick-reply, grr... okay, based on the size and shape of the pack, and the LED configuration as best I can tell from online research sources (2x3W, typically 2x3.6Vx0.7A), your battery pack is likely 5x(4/3A)1.2V cells (6V total pack voltage).
The LEDs need higher than pack voltage, so there must be a boost circuit involved. The LEDs by design are probably around 20-watt hours (for a 4-hour runtime as rated), meaning around 3300mAh for the 6V pack.
Bottom line, if it was a true 4-hour runtime when new, these are probably 3600+mAh 4/3A cells (pack looks longer than fat, otherwise I'd say sub-C cells). There must be a boost circuit, if the pack output connector reads around 6V typical (up to 7.0V hot off the charger), then the boost circuit is likely in the light-head.
Either way, its' a great pack to start with for a new LED design, just make sure your design is regulated appropriately. Get a multimeter (cheap will work for basic stuff) to test the pack voltage with.
By nature, packs that ran older LED setups well, will run new LED setups even better as the LEDs have improved in efficiency.
Good luck!

 

[BrianMc]

:welcome:

As an owner of a different old Cygolite battery (12 v nominal NiMH), I was bemused after actually testing it to find under the mounting strap of the water bottle mount battery case, a label with the nominal voltage.

The manual and box also claimed a 5 ahr rating (if you have either, this is worth a shot)

If you are going to rebuild this light, you are going to need a multimeter to test that your soldering and continuity. Beware! circuit testing is addictive, almost as much as the first flare of light form your first light. The next thing you know you'll be building lights for Christmas presents! :santa:

The neat thing is that as the NiMH ages and loses capacity (about 10% per year), the efficacy of the LED's increases so an LED swap can extend battery life a little longer. Meanwhile, battery technology improves and becomes less expensive, so you don't have to put up with a low run time unless you really want to.

 

[4thpage]

Thanks for the info, folks! I'm going to check the currents and voltages coming off the battery and off the emitter tonight. I'll let you know what I come up with.

If I decide not to use this pack, know any vendors who sells oem-looking packs (i.e. durable, weather-proof casing and cabling)?

Thanks, again! :thanks:

 

[4thpage]

Okay, here's what I got:

From battery:
5.63 V right after charging
18.19 A (battery pack clicked after about 2 seconds, and Amps dropped to 0. Is this some sort of protection circuit kicking in?)

From Lumiled LEDs on high setting:
3.25 V each
2.02 A each.

So, what does this tell me? How can it be that these batteries could put out 2020 mA for the 4 hours the manufacturer rates them at?

Does it seem that the LEDs are being underpowered with voltage of only 3.25 each?

 

[4thpage]

Okay, so I just realized, after being curious about my current readings and doing a little research, that the way I was attempting to measure the current was all wrong. Somehow I managed not to fry anything...whew!