Electronics, Lighting, & Gadgets - Light/Battery experts...enter here...

Okay, so I have an older TurboCat light that's just laying around. The light/head itself is fine, but the lead-acid battery is kaput. It holds a charge for about 15 minutes.
The head throws a lot of light...more than my MiNewt X2...as well as a much warmer and wider beam.

Here's my question and where I'm hoping someone can help...

Is it possible to build/buy a li-ion, or ni-mh, battery to run the TC head? I know NOTHING of these things.
My light is an older S10, so I think it's a 6v battery. I'd like to make it into a setup that I can run on the bars, or helmet, thus the need for a light and small battery.

Thanks in advance!

M

Sure. go to batteryspace.com (or other such vendor), pick out a pack+charger that meets your needs. You won't hit the voltage exactly with LiIon because the cells 3.6v each, but going to 7.2v won't hurt the light.

Assuming it's a 10W bulb, at 6 volts that's 10/6=1.666 amps of draw. If you want a 1 hour runtime, you need at least a 1700mAH pack (though it's not good for modern batteries to run them dead every time, so they'd last longer if you got more capacity than you need).

For LiIon, there are some choices here:
http://www.batteryspace.com/capacity2000mah-5200mah.aspx

Basically about $55 plus shipping, call it $65, and you'll have to do some soldering.

You could go with NiMH off this page for a little cheaper:
http://www.batteryspace.com/6v-battery-packs-from-2200mah---5000mah.aspx

Personally my opinion is to give up on that, for $80 shipped you could just replace it with a Magicshine that would put out more light, not have a bulb that's subject to burning out, had multiple output modes and strobe mode, and a 3 hour runtime. I've got a 20W halogen and a 13W HID system that are just sitting around unused, because neither of them are nearly as nice as the Magicshine light, and even the HID doesn't put out as much light (the HID used to put out about as much but is now old).

Sure. go to batteryspace.com (or other such vendor), pick out a pack+charger that meets your needs. You won't hit the voltage exactly with LiIon because the cells 3.6v each, but going to 7.2v won't hurt the light.You might hurt the light.

A 6v lead-acid battery goes up to, what, 6.9 volts? Two LiPo cells goes up to 8.4 volts. That's a 22% increase in voltage, so a 48% increase in power (assuming that resistance is a constant, which of course it isn't, but it's a convenient approximation.)

Ultimately, it will be brighter than it was before (unless it has a regulator of some sort.) It may burn the bulb out quickly, and if not, it will certainly make it last a shorter period than it did before.

You could add a voltage regulator (or even better, a DC-DC converter that emits the right voltage more efficiently) and keep the voltage down to between 6 and 7 volts.

If you go with NiMH cells, 5 cells is probably a very close match to your lead-acid battery. (6 cells is almost exactly a match for 2 LiPo cells.)

You could also replace the lead-acid battery. You don't need the exact same size -- just something close, 6 volts. It could even use your existing charger.

I wouldnt term myself an expert by any means, but building a battery pack is not that hard. In looking at the TurboCat website, IF your rig is an S10 then it is a 6V system (you'd want to be sure of that). It does look like the 13.2V systems are all double lights.

I dont know how you would go about building a "macho" SLA battery, but it would be fairly easy to get a replacement for the 'MRF' (NiMH) type system - and for LOTS less than the $180 they want. There may be a trade off in runtime depending on your approach.

The problem with this approach is usually the connector - they are often proprietary. In a perfect world you could just solder the connector from the old battery to a new NiMH pre-assembled pack. In this case, you probably also want a new charger. I dont know how SLA chargers work, and since they (appear to) supply different ones for SLA vs NiMH packs, I would just get a new smart charger.

But fear not, it is still pretty easy and even with the charger you can get a new NiMH pack for about half the price of a new SLA.

If you are squeamish about DIY electronics you can get a "kit" of a high-cap battery pack, charger and the required cables and connectors for about $80. The pack capacity is 10Ah so run time on it would actually be about 40% more than the original SLA. The only down side is that the high cap battery pack is about 2 lbs. Batteryspace (http://www.batteryspace.com/nimhbatterypack6v10ahflattrail-techfemaleplugforbikelightsmartfastcharger48-108v.aspx)sells such a kit.

For even less money, you can get essentially the same kit in a 5Ah version (http://www.batteryspace.com/nimhbatterypack6v5ahflattrail-techfemaleplugforbikelightssmartfastcharger48-108v.aspx) for $50 (and less than 1 lb). Runtime should be about 2h - 2h 20m.

In either case, you would need to replace the connector on the light so it mates up with the new pack (which is about the minimum of work you are going to get away with - short of getting someone else to do it :lol:). Either replace the cable from the light at the head with the one supplied or splice it in. Then just find a bag for the battery. If you splice it in, buy some PVC shrink tubing from their DIY section to help protect the splice.

Alternatively, you could buy the parts and build your own. I would opt for a 5 cell, 4/3AF pack. You can get these already assembled so that all you need to do is solder on the lead. The packs come in various capacities but the one I usually use is the 4500mAh. Add in the smart charger, a cable for the light and a cable end for the charger (I would suggest Trail Tech) and you've got it for about $65. There is more work involved, but the AF packs are flat and EASILY fit in a variety of camera bags. My affinity for this approach is that it allows me to mix and match chargers and carry bags etc across any light system I have now.

HTH!

Turbocat states that they use 5v bulbs, so the 6v battery is already over-clocking the bulb's output. Would jacking it up to 7.2 (or even the 8+ number) blow the bulb like a flashbulb?
I'm looking for right at two hours of runtime. I feel confident in my ability to cut and solder the new lead onto the head.
I'm going to look at the stuff on batteryspace right now...

If you are interested in Li-Ion, look at battery space's regulated 5/6V packs (http://www.batteryspace.com/5vand6vregulatedli-ionpackmodules.aspx). Steps down the volts to a level unlikely to damage the bulb and/or head. This too has a pre-assembled pack available (http://www.batteryspace.com/li-ion18650battery6vregulated3256wh1aratebatterypackwithtrial-techfemaleplug.aspx) with a TrailTech connector.

Li-Ion will give you a LOT more runtime for the bucks (about 5x that of the original SLA) and with less weight, for only a bit more money. This uses one plug to charge and one for the light. It isnt a kit, so you have to add in the connector for the light and a charger separately.

Pricier than NiMH but LOTS more runtime.

Just bought a Magicshine...hard to beat for $90 shipped...

Turbocat states that they use 5v bulbs, so the 6v battery is already over-clocking the bulb's output. Would jacking it up to 7.2 (or even the 8+ number) blow the bulb like a flashbulb?
I'm looking for right at two hours of runtime. I feel confident in my ability to cut and solder the new lead onto the head.
I'm going to look at the stuff on batteryspace right now...

Well, not like a flashbulb, but if they're already overvolting, I wouldn't go to a 7.2v LiIon pack, because they'll be closer to 8 volts when fully charged.

I'd go with NiMH, a 6v pack, which would be 5 x 1.2v cells. I have a NiMH bottle battery that ran both my HID and my halogen for a couple of years, and is still in fine shape; I'm thinking about moving up from my Dinotte 140L to a Nova police car type LED pack on the back, and also use the 12v to run an actual car horn.

Just bought a Magicshine...hard to beat for $90 shipped...

If you have the time and money, you could whip together a NiMH battery pack for the TurboCat to sell on eBay. I got started building battery packs because I had all these working lights but no batteries. Built several NiMH packs and sold the lights on eBay for about 150% of the cost of the pack meaning I was able to recoup part of the original cost of the light.

Well, not like a flashbulb, but if they're already overvolting, I wouldn't go to a 7.2v LiIon pack, because they'll be closer to 8 volts when fully charged.Just for the record ...

LiPos start at 4.2 volts/cell fully charged. So that's 8.4 volts for two cells, and it's down from there.
NiMH and NiCd start at 1.4 volts/cell fully charged. So that's 7.0 volts fully charged, and it's down from there.
Lead cells start at about 2.1 volts/cell fully charged, so a 3 cell battery (aka 6v) is 6.3 volts fully charged, and it's down from there. (I was wrong about this figure earlier.)
Alkaline batteries start at 1.5 volts, and it's down from there.

The 3.6/1.2/2.0 volt figures you hear are nominal ratings -- when you hit that point (at a low rate of discharge), your battery is like 40-60% discharged at that point for LiPo, NiCd and NiMH. For lead acid, it's less than that.

This is a bigger issue when comparing akalines to rechargables, as the 1.5v alkaline rating is a fully charged battery, but a 1.2v NiMH is about half charged, but it's still something to keep in mind when you're figuring out the voltage you're working with.

But I agree about going with a 5 cell NiMH pack -- slightly higher voltage than the stock pack, but not much more. But you'll need a new charger if you don't have one.

Though I agree even more with his decision to just buy the Magicshine rather than spend a significant portion of it's cost on new batteries and a charger for them -- more light, longer runtime (in lower modes), probably lighter, likely to behave better as the battery discharges ...

Thanks guys...rather than spend the $ to buy/build a battery and charger, I figured I'd just pull the trigger and buy the Magicshine for the same $.
I may still buy a battery for the TC. Seems like a waste to just let it sit and gather dust.

5 Nimh D cells would give you 6.25 volts and a pretty good run time.