Since we are talking about the lamps again, here's a seller on ebay that is asking too much for a Koehler lamp but it really is a great deal. Why? Because it is a Lithium-Ion style Mark V with charger. The lamp with battery sells new for $350 and the charger another $245.

http://cgi.ebay.com/KOEHLER-WHEAT-MINING-COON-HUNTING-LIGHT-and-CHARGER-/230540156015?pt=LH_DefaultDomain_0&hash=item35ad439c6f#ht_484wt_1156

I have been thinking about converting my lead-acid MkII's and MkV's to the Lithium-ion setup but have been deterred by the cost. I was even looking into the possibility of obtaining some Li or some NiMh cells and building a battery pack into a gas tight enclosure. Does anyone have more detailed specs on Koehler's Li battery other than what is on their website? I would like to find some amp-hour ratings and maximum charge/discharge rate specs as well.

Lastly, does anyone know if the new Koehler Li battery will work ok on an older style charger as is commonly used with the 5000 series batteries?

thanks,
rh

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"If we knew what we were doing, it wouldn't be called research." -A. Einstein

All batteries need to be vented to some degree when charging or else BOOM! Lithium-Ion can very dangerous when charging. That's why chargers for them are "smart" type and most cells are "protective". They contain a small circuit that shuts down when the battery moves outside the safe range of 3–4.2 V. They can also suffer from thermal runaway. If discharged (used to power a device) too quickly compared to their rating capacity, they can explode. So enclosing them in a sealed, gas-tight enclosure may not be advisable.

The Li-Ion 18650 cell is rated 3.7 volts and available in capacities from 2000 to 4000 mAh but I would stick to 2000-3000 mAh for reliability. When added in parallel, the capacity will be very high.

Info can be found on their website here http://www.koehlerlighting.com/pdf/LI-16.pdf

The Koehler battery rated at 16 Ah, so 8 2000 mAh or 6 2600 mAh would equal the same capacity.

I am sure the charging plug on these lamps are incompatible with the regular chargers, unless the charger is actually located within the battery or lamp head. But like esaresky75 says, lithium ion packs have protective circuits to prevent over charging and over discharge of the battery. The charger runs at a constant voltage, but when the batteries reach their normal full charger voltage, the battery is only 70% charged. The charger than drops the current for the remaining of the charge. These batteries are very picky and kind of dangerous... They need to be charged with the right charger unless they include the charger inside the lamp so that you can use a normal charging rack.

Miner Greg

Yes, the Koehler Li-ion lamps have the same headpiece charge connection as the normal ones. What I am not certain of is if they have the smart-charge chips in the battery itself...this would make sense, as it would provide the required safety and not require the mine operator to replace a charging station to accomodate the new Li-ion lights.

After much research, I have found that the Hawker (formerly Gates) CYCLON sealed lead-acid cells are a very good alternative. They have fully sealed, intrinsically safe capabilities without the worries of the lithium cells. They have a nearly 100% recovery cycle so do not require venting in any phase of operation (a relief valve is fitted to the cells just in case of severe overcharge)

The weights and capacities are similar to the liquid filled Wheat lead acid batteries as well. Two of the Cyclon 4v, 8AH packs can be wired in parallel for the 16AH capacity and will weigh about the same when fitted into a Pelican 1060 case. This is a sealed case with a purge vent for safety and the latch could be opened when the lamp is put on charge. Operationally, it would be nearly identical to the traditional Wheat battery......and much cheaper.

Furthermore, the tech specs for the Cyclon show that in the charge/discharge range of these lamps, the service life would be about 1500-2000 cycles....a bit better than the old Wheat batteries, and possibly better than the new lithium ones as well.

The lithium batteries do have greater capacity per pound, but the finicky charge/discharge circuit chips may not make them desireable in a place where the light MUST run or where some rough handling can occur. (I've had IC's fail many times due to surges, static, etc so I prefer to limit their use to non-critical places.) Still, I may eventually build a lithium pack to try if I can find a good deal on the 18650 cells.

I may make up one and see how it goes....if good, then I will probably replace the others as they reach their end of service life as well.

thanks,
rh

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"If we knew what we were doing, it wouldn't be called research." -A. Einstein

You can charge the lithium battery using your original charger. Talked to a rep about this last year. The upgrade for your existing lamp is a new battery and cord, you keep your existing headpiece and related charger. Screw the nre cord into your headpiece and youre good to go. The charging circuitry is in the cap on the battery with a status led. When my battery pukes this is the route im going.

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i know northern light just came out with a completly wireless lamp.....looks like/is the size of a koehler lamp head just with no cord has a small lithium battery in it that last i think 12-14 hours........probably has a pretty price tag too

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Yes, I was looking at those...it is the "Polaris" and has an MSHA approval too.....they run about 300 bucks, plus another 60 or so for the charger.

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"If we knew what we were doing, it wouldn't be called research." -A. Einstein

banks told me about one of those he saw at some active mine between here (pa) and alaska, cant remember where. said it was real front heavy......

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I would like to try one of those, but I am skeptical that such a small battery would last 12 hours.

http://www.strataworldwide.com/usa/safety-products/polaris-caplamp.htm

They must include the charger and protection circuitry inside the battery of the L-ion Wheat Lamps. So your charging rack puts out it's normal voltage, and the charger inside the battery picks up the smart charging of the L-Ion battery. Then it shuts the charge off when the L-Ion battery is full. Certainly not difficult to do..

The thing is that some of these new Cells that are out put out a lot higher amp than the old Lead Acid batteries. They are just a little more trick to charge than the constant charging you could do on the old lead acid batteries..

Miner Greg

I agree with you that the NL Polaris may feel nose heavy, it just makes sense that it would.....still, I might like to try one some day. Due to the small size, it seems like it would be a good one to put in a pocket as a backup light....I think you can also get clips and/or magnets to attach it in other places, so it could be quite handy depending what you are doing.

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"If we knew what we were doing, it wouldn't be called research." -A. Einstein

Our mine tried out the Northern Lights Polaris- Some people like them a lot, but the mine ultimately decided not to run them. Of the 12 we bought 10 are still working, and of those 2 or 3 are broken and "repaired" with electrical tape. I've got some comparison pictures on my website of them versus the standard wheat LI-16.

http://www.vulcanlux.com/comparisons.html

Ultimately the mine decided to go with some replacement bulbs I invented to convert the Wheat's to LED.

That is a pretty interesting lamp conversion...I plan to browse a little more through your site as time permits. However, I must take issue with one point I saw on your page: You stated that there is a 5% state sales tax in Alaska. This is simply not true. You may have a local tax in Juneau, but in Fairbanks, Anchorage, or many other places this does not apply. In any case, it is an interesting item and I am looking forward to reading more about it. Thanks.

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"If we knew what we were doing, it wouldn't be called research." -A. Einstein

Thanks for pointing that out. Yes, its Juneau only sales tax. Thanks for the feedback.