Electronics, Lighting, & Gadgets - Magicshine Battery Maintenance Question

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datlas
09-20-10, 07:05 PM
I got a first generation MS-900 last x-mas from geoman. Love the light.

But the battery died.

Here is my experience:

Initial burn time was 3 hours - sweet!

After just a few (maybe 5-6) cycles, burn time dropped to 1 hour, not so sweet but ok.

After another 6 cycles or so, the battery died....it just wouldn't take a charge, the charger LED was always red.

I wrote to geoman and they VERY KINDLY sent me a new battery last month. This one is the newer battery (cylindrical shape).

I want to do right by the new battery, and am wondering the following (forgive my ignorance but I am not knowledgeable about batteries):

1. Does it matter if I let it run down between charges? Or just top it off?
2. Does it matter if I keep battery and charge it in my garage (winter temps about 45F).
3. Anything else I can do to maximize battery life and minimize it from dying an early death?
4. I plan to disconnect the battery when not in use (so the stupid LED is not on), is that best or should I keep it connected or does it not matter??

For my backup lights (fenix L2D CE Q5) and blinkies I have a smart charger from Lacrosse, but for the MS I just have the dumb charger and would appreciate any suggestions/answers to the questions above.

Thanks!

Doug


ItsJustMe
09-21-10, 05:30 AM
First off, there was definitely something wrong with the first battery. The battery has circuitry inside the pack to prevent you from doing anything to it that will damage it that badly. It is not supposed to allow either overcharge or undercharge. So don't be concerned that you did something to damage it (unless you drove a nail through it, or got it wet or something).

The "ideal" for LiIon storage is to charge them to 60% and leave them like that. But that's for long-term storage. For a few hours or days at a time I don't think it matters much. I would not leave a LiIon cell totally discharged for long, that's the worst thing you can do to them. If you do run one flat, charge it back up ASAP. If it's not down to where the light turns off, don't worry about it, charge when you get a chance.

45*F temps are NOT an issue. I've left LiIon batteries outside in subzero temps overnight and they didn't die. They don't LIKE it, but their dislike is limited to just not providing much power while they're actually cold.

As far as disconnecting, I don't think it matters much as long as you don't leave it connected for so long that it totally discharges the battery. Again, the battery's internal circuitry should prevent cell damage, but you never know.

If you're disconnecting regularly, be very careful of the connector. Even the best connectors will get damaged if you unplug and re-plug them hundreds of times a year if you at all pull on the wire rather than the connector. I personally do disconnect twice a day, but I'm extremely careful to grab ONLY the connector, and I do not twist more than necessary to get them apart.

The charger that comes with the MS is NOT a "dumb charger" - if you were to use a "dumb charger" on a LiIon cell, you'd wind up with a fire; you simply can not charge a LiIon without a smart charger. It's probably not a brilliant charger, but it's not dumb. The lack of an LCD panel does not mean it's not a smart charger. I leave mine plugged in overnight regularly and nothing gets hot or anything. I've left it plugged in for a few days before too, and no problems. Besides, again, the circuitry built into the pack itself will prevent overcharging so you don't have to worry about that.

datlas
09-21-10, 05:56 AM
^^ Thanks!!


ItsJustMe
09-21-10, 07:21 AM
To clarify, running a battery until the light shuts off then not charging it for a day or two won't hurt it. What you do not want to do is to allow the per-cell voltage to get below a critical level. The circuitry inside the battery will stop it discharging before it gets to this level. The only danger is if you let it get that low, THEN let it sit for weeks or months, during which time it may self-discharge below the critical level.

If the voltage per cell gets too low, it can crystallize the electrolyte within the cell, and the part that becomes crystallized no longer is able to hold a charge.

RT
09-21-10, 07:48 AM
Agree with ItsJustMe, and I had the same experience as the OP. The new battery rocks. I charge mine every other trip (about an hour or so of use), and if I allow the light to go idle for more than a week.

socalrider
09-21-10, 09:39 AM
I have had my ms light for over a year and I am seeing lower runtimes than when I bought it but that is the norm for all lights.. It is always a possibility that you have just 1 bad cell in the 4 cell battery pack and this is the problem. Due to the price, I'm sure they are using low cost 18650 cells in the battery packs..

I always top my battery off before riding, just in case I get adventurous and decide to ride for 2-3 hours.. I always have someone extra on my bars in case the battery runs down, it has only happened once on 3 hour ride, switched to the lower mode to preserve battery once the red light came on..

AltheCyclist
09-21-10, 01:21 PM
Just curious, so, it seems the "older" (non-cylindrical MS 900 model) batteries have had problems? Mine is about year old and doesn't hold much charge, I chalked it up to being a crappy battery. Sounds like others have ran into this?

ItsJustMe
09-21-10, 03:34 PM
Just curious, so, it seems the "older" (non-cylindrical MS 900 model) batteries have had problems? Mine is about year old and doesn't hold much charge, I chalked it up to being a crappy battery. Sounds like others have ran into this?

I'm assuming that they're all the same thing, the cylindrical model is just the old one, well, shoved into a cylinder. Mine is a year old and it does fine. However, I did buy an aftermarket 8 cell pack (not from MagicShine) and I mainly use that now, because with that I only have to charge up once a week even with the taillight running too.

I almost wish my old pack would have died, if the new packs with the hard plastic shell and the battery gauge were available for a good price! But it's still running fine.

colleen c
09-21-10, 05:19 PM
Just curious, so, it seems the "older" (non-cylindrical MS 900 model) batteries have had problems? Mine is about year old and doesn't hold much charge, I chalked it up to being a crappy battery. Sounds like others have ran into this?

My battery pack went through about 25 charge/discharge cycle since near the end of March this year. I charge them once a week because I use them for 2.5-2.75 hours a week. The first 20 cycle, I were getting at least 2.5 hrs before recharging. The last 5 cycle, I get less than 1.5 hours of run time.

I doubt the new battery will be any better than the old one unless they used better 18650 cell so that they are better balanced and less mismatch in the 2S2P hookup, but base on the price I kinda doubt that and issue such as diminishing run time from the pack going bad will be a common thing.

xizangstan
09-21-10, 08:09 PM
I'm probably asking a biased crowd here, but is the MagicShine (sounds like shoe polish) that much better than the other lights out there? Would you buy another?

ItsJustMe
09-22-10, 05:11 AM
I'm probably asking a biased crowd here, but is the MagicShine (sounds like shoe polish) that much better than the other lights out there? Would you buy another?

For the price, yes, it's very much better than other similar lights, especially in their current generation. In the sub-$100 range, the only other competitor is high powered flashlights like those using P7 LEDs. A P7 flashlight with charger, batteries and mounting will run you in the neighborhood of $65 or so, and for $80 you can get the Magicshine.

The pros on the Magicshine are that it has a 4 cell pack which gives a 3 hour runtime, and the beam pattern is pretty good (with the caveat that it's a conical beam, but that's true of pretty much every light sold in the US). Flashlights are a little cheaper but the runtime is typically only 1 to 1.5 hours per battery change. That's plenty for most people if they don't mind changing the battery after every ride.

The MagicShine's actual light output is somewhere in the 450 to 550 lumen range (manufacturers love to exaggerate- the 900 lumen rating is just what the LED is rated at)

To equal the Magicshine's light output with name-brand lights, you have to go into the $200 to $300 range at least. Some people argue that you don't need that much light, and depending on your situation, that could be true. Personally I ride regardless of weather, and when I'm riding at 4AM through heavy fog or heavy rain, I do feel like I need that kind of power.

They also have a taillight that can run off the same battery pack; this is a bonus for me - I was getting sick of having to charge two battery packs.

If price is no object to you, or if you are not comfortable with or feel it's not worth your time to deal with things that might be less reliable, then perhaps a name brand light (at 3 or 4 times the cost for the same functionality) is a better light for you. Personally, all I've really had to do with my MS light is to solder on a new connector after a year or so, and wrap a plastic bag around the battery. To me it was worth saving over a hundred bucks for that 15 minutes worth of work.

I would not ride with only one light even if I paid $1000 and had the best light on the market. I've had my light fail (not the MS) in the middle of the night with no backup; in that case I wound up using my Dinotte taillight to see where I was going. It was nerve wracking and I don't care to repeat that, so I now run with a P7 flashlight on the bar as a backup. It also serves as a light to use when running errands, since the MS battery lives in my panniers and I usually don't bother mounting it when running out for a sandwich or something.

MagicShine had issues in their first generation; the connectors and wires were a little flaky and the battery pack was not waterproof. Those issues have been addressed. What they have not addressed is the fact that their battery packs are made from pretty cheap cells, which means that after a year or so of use they're losing runtime. This affects different people to different extents - my pack is still running great after a year, some people have lost half their runtime after a year. However, given the fact that replacement packs are $40, and similar replacement packs from name-brand manufacturers might cost $120 or more, you could buy a new pack every year and still probably be ahead on that score, because all packs die eventually.

datlas
09-22-10, 12:31 PM
I'm probably asking a biased crowd here, but is the MagicShine (sounds like shoe polish) that much better than the other lights out there? Would you buy another?

Yes. As ItsJustMe stated much more eloquently than I could, it's a good light. If you want a fairly bright light and you are on a budget, it's the best bang for your buck headlight.

It's not perfect but I would buy another in a heartbeat.

There are certainly better lights out there but you would have to pay three times the price.

RT
09-22-10, 01:07 PM
Some people argue that you don't need that much light, and depending on your situation, that could be true.

The main reason I own a Magicshine (aside from this board recommending it) is an unfortunate encounter with a wayward rabbit at 4:30 a.m. on a commute which involved an endo, and not in a good way. I was using a CatEye EL320 at the time, and my accident made clear the need for more illumination. Magishine provides that. If I am anywhere on my ride at dusk, dawn, or dark, I mount the 'Shine. Absolutely a necessity, based on practical (and painful) experience.

buzzbee
09-22-10, 02:19 PM
Like others, I had older lights that did not produce much light, like the EL320, especially not enough spill light. I like the idea of more than one light, in case batteries fail in one. The Magicshine is good, I use it most of the time on the low setting and get at least 6 hours of run time before I recharge.
Like the OP, I also have some Fenix AA flashlights mounted, these are not as bright and have less run time, but are good backups, and are useful off the bike for camping, exploring. I have never owned a more expensive bike light, so I cannot compare except to say the Magicshine is rather low cost for a bright bike light. There are beam comparison photos out there on the web.

After 11 months, I have not had any issues yet with the MS battery, but all batteries eventually develop less capacity and then fail. In truth, I have had many capacity issues with the Nimh AA batteries I've used, so the charger I now use for them (like the OP) allows for the test of individual batteries, and refresh if needed. The MS battery pack does not allow for this kind of testing, but so far, no issues... The MS battery pack is four 18650 cells in series/parallel, so one bad cell mean half the capacity, which is still better than the AA battery lights where they are all wired in series, so one bad battery and the light gets very dim.

colleen c
09-22-10, 09:08 PM
Yes I will buy another MS only because I have the option of not using their battery pack. If I had to do this all over again, I probably buy the tail light with the battery and a light head only without a battery. I use the MS battery only for the tail light and buy an another pack from elsewhere or build my own pack using holder such that I can recharge each battery individually in a charger to keep them all balance and less problematic.

ItsJustMe
09-23-10, 05:54 AM
Yes I will buy another MS only because I have the option of not using their battery pack. If I had to do this all over again, I probably buy the tail light with the battery and a light head only without a battery. I use the MS battery only for the tail light and buy an another pack from elsewhere or build my own pack using holder such that I can recharge each battery individually in a charger to keep them all balance and less problematic.

That's actually not a bad idea, however, I'm too damned lazy to want to take cells out of packs to charge. I was doing that for my Dinotte AA and it drove me batty. Also having a combination of removable batteries AND waterproof would make it even more troublesome to get the batteries out.

I actually use an 8 cell pack that I bought from some other place when they had them on sale last year for $25 - I think many others here bought one at the same time. The connector on that wasn't exactly right and it was very intermittent. I wound up soldering on an actual MS connector.

These days my battery pack is in a plastic bag and just lives in the bottom of my pannier with a wire sticking out the top. I haven't seen the actual battery for weeks. I know the pack would last longer if I took the cells out and charged them individually, but given that it lasts a couple of years anyway, I'm too seduced by the convenience of just "plugging in" my pannier at my desk at work once a week, and that's the extent of my regular maintenance.

davidad
09-23-10, 04:12 PM
http://www.batteryuniversity.com/parttwo.htm

Garfield Cat
09-24-10, 07:29 AM
If one had to re-design or re-configure the power supply for the MagicShine 900, what would be "best"? Wouldn't one big battery be better than 4 batteries hooked up in series/parallel?

Richard Cranium
09-24-10, 08:33 AM
If one had to re-design or re-configure the power supply for the MagicShine 900, what would be "best"? Wouldn't one big battery be better than 4 batteries hooked up in series/parallel? I don't know what you want the battery to do. But the simple facts are using a 4x18650 format makes the most sense from a mounting, power, run time or any other measure. Here is one of the best deals going. (http://www.batteryjunction.com/tenergy-74-4400-pcb.html)

PS - this battery should break the 3 hour run time mark - maybe 3.5 hours on high - continuous!!!

PS again - the reason battery cells are made like 18650 or "AAs" is because of the physics and chemistry of how minerals ionize. As soon as you start making cells the - like "D" size or bigger - problems develop with how the chemicals can disperse and hold "ions" evenly.

Otherwise - giant cells the size of coffee cans would already be made - but they just won't work well - they would have "hot and cool" spots of electrolytic material.

myrridin
09-24-10, 09:07 AM
I'm probably asking a biased crowd here, but is the MagicShine (sounds like shoe polish) that much better than the other lights out there? Would you buy another?

I think the quote; "if you are not comfortable with or feel it's not worth your time to deal with things that might be less reliable, then perhaps a name brand light (at 3 or 4 times the cost for the same functionality)" says it all.

Part of the reason other (name) brands cost more is that reliability is part of the functionality. Others are you don't need to arrange your own water resistent packaging for the battery pack, etc...

A light is a key safety element when riding in dark conditions, if your comfortable with it failing and willing to deal with the consequences, then it may be a good choice to save $100-$300. Certainly if you can't afford the better (more reliable) lights then it is better than nothing).

ItsJustMe
09-24-10, 09:19 AM
If one had to re-design or re-configure the power supply for the MagicShine 900, what would be "best"? Wouldn't one big battery be better than 4 batteries hooked up in series/parallel?

It would have to be two big batteries. One big battery would only give you 3.6 volts, not 7.2 volts. Then you're back to charging in a serial arrangement and that's actually probably the biggest problem. Two batteries in parallel will be forced to stay in sync with one another, and as long as one isn't vastly worse than the other, probably not a big problem.

The other problem is that in order to maintain the economy of the thing, you want to use commonly used batteries that are made in the hundreds of thousands. 18650s have GOT to be the most common LiIon cell in the world, by a huge margin, because it's the cell used in laptop computer packs and other things. As soon as you switch to a different cell, you're probably going to double your cost right there.

ItsJustMe
09-24-10, 09:23 AM
Part of the reason other (name) brands cost more is that reliability is part of the functionality. Others are you don't need to arrange your own water resistent packaging for the battery pack, etc...

A light is a key safety element when riding in dark conditions, if your comfortable with it failing and willing to deal with the consequences, then it may be a good choice to save $100-$300. Certainly if you can't afford the better (more reliable) lights then it is better than nothing).

It's questionable whether this is much of an issue anymore anyway. Even with my first generation light, the only time it failed was a year after purchase, after hundreds of uses. It was a bad connector, I replaced it, and it's up to dozens of uses again since then and I expect it to last many hundreds more uses at least.

With the new generation, the wires are more reliable (so expect problems less than once a year under constant use) and the battery has been fully waterproof for the last two entire generations of lights. And in any case, the solution was "put battery in heavy plastic bag, put a zip-tie around mouth of bag with wire coming out, tighten. 10 seconds, and it's fine in heavy rain now. I don't think it's particularly worth harping on, and it's especially not now that it's not been an issue for this light for over 6 months now.

Talking to someone considering a new light purchase about shortcomings that have already been fixed with the current generation of lights is not helpful to anyone. It really makes it sound like you're just grasping at straws.

There are many things to consider when purchasing lights. One thing is that, honestly, hardly any person who's just getting started riding is going to go right out and spend $200 to $400 on a headlight. Even $80 is probably pushing it. Now that really good, bright lights that car drivers notice and respect are available for < $100, I think it's sensible to try to convince people who otherwise would be buying $35 wimp lights to make the extra investment in safety.

If the message being pushed is that the $80 light is a complete piece of crap that will fail when you most need it, and they really should be buying a $250 light instead, most people are not going to buy the $250 light, they'll buy the $35 light instead. This is not doing them any favors.

I don't personally feel that ANY light, even a Lupine, is reliable enough to not carry a backup anyway, so I may as well save the money. I carry a P7 flashlight on my bar at all times as a backup. The one time my MS failed a few weeks back, I just reached down and hit the flashlight switch. I was without light for 3 seconds.

myrridin
09-24-10, 10:06 AM
It's questionable whether this is much of an issue anymore anyway. Even with my first generation light, the only time it failed was a year after purchase, after hundreds of uses. It was a bad connector, I replaced it, and it's up to dozens of uses again since then and I expect it to last many hundreds more uses at least.

With the new generation, the wires are more reliable (so expect problems less than once a year under constant use) and the battery has been fully waterproof for the last two entire generations of lights. And in any case, the solution was "put battery in heavy plastic bag, put a zip-tie around mouth of bag with wire coming out, tighten. 10 seconds, and it's fine in heavy rain now. I don't think it's particularly worth harping on, and it's especially not now that it's not been an issue for this light for over 6 months now.

Talking to someone considering a new light purchase about shortcomings that have already been fixed with the current generation of lights is not helpful to anyone. It really makes it sound like you're just grasping at straws.

There are many things to consider when purchasing lights. One thing is that, honestly, hardly any person who's just getting started riding is going to go right out and spend $200 to $400 on a headlight. Even $80 is probably pushing it. Now that really good, bright lights that car drivers notice and respect are available for < $100, I think it's sensible to try to convince people who otherwise would be buying $35 wimp lights to make the extra investment in safety.

If the message being pushed is that the $80 light is a complete piece of crap that will fail when you most need it, and they really should be buying a $250 light instead, most people are not going to buy the $250 light, they'll buy the $35 light instead. This is not doing them any favors.

I don't personally feel that ANY light, even a Lupine, is reliable enough to not carry a backup anyway, so I may as well save the money. I carry a P7 flashlight on my bar at all times as a backup. The one time my MS failed a few weeks back, I just reached down and hit the flashlight switch. I was without light for 3 seconds.

I have no personal experience with the Magicshine, though I do have experience with cheap chinese products...

That said, I haven't seen a single Magicshine user recommend the light without qualifiers... Great light for the price. Best Bang for the buck. Or the quote of yours that I used...

If all you can afford is an $80 light, then it is certainly better than nothing, or the other alternatives in that price range... But someone buying a $1,000+ bike can likely afford a more expensive (and better built) product and will likely do so, after being unsatisfied with any (or all) of the quirks that warrant the users qualifications about the light.

If someone asks the question; "What is the best light under $100" The answer is almost certainly the Magicshine
When the dollar value hits $200 the answer is less certain, and by the time it hits $300 it is almost certainly not the Magicshine.

ItsJustMe
09-24-10, 11:28 AM
If someone asks the question; "What is the best light under $100" The answer is almost certainly the Magicshine
When the dollar value hits $200 the answer is less certain, and by the time it hits $300 it is almost certainly not the Magicshine.

Even that depends on the goals of the purchaser and what they mean by "best". If they mean "brightest" then the answer is the Magicshine 1400. You can't buy any light off the shelf for less money that's brighter.

If they mean most reliable, then you're correct, it's very likely that the Dinotte 400 or some of the lights you've talked about are more reliable.

It's like asking "what's the best bike" for a given amount of money. There's no one answer.

For me, the "best" light for $200 is the Magicshine at $80. I want that level of brightness and without spending more than $200, I can't get more light than the MS light. And honestly, I don't think I need more light that that, so I don't personally want a MagicShine 1400, or even a Lupine Wilma or something crazy like that.

If you put a MagicShine and a Wilma on a table and said "pick one, either one is yours for free" of course I'd take the Wilma. Then I'd hit eBay, sell the Wilma, buy a MagicShine and buy a new bike with the difference.

myrridin
09-24-10, 04:13 PM
Even that depends on the goals of the purchaser and what they mean by "best". If they mean "brightest" then the answer is the Magicshine 1400. You can't buy any light off the shelf for less money that's brighter.

If they mean most reliable, then you're correct, it's very likely that the Dinotte 400 or some of the lights you've talked about are more reliable.

It's like asking "what's the best bike" for a given amount of money. There's no one answer.

For me, the "best" light for $200 is the Magicshine at $80. I want that level of brightness and without spending more than $200, I can't get more light than the MS light. And honestly, I don't think I need more light that that, so I don't personally want a MagicShine 1400, or even a Lupine Wilma or something crazy like that.

If you put a MagicShine and a Wilma on a table and said "pick one, either one is yours for free" of course I'd take the Wilma. Then I'd hit eBay, sell the Wilma, buy a MagicShine and buy a new bike with the difference.

Yep, I understand what you are saying. For me, I ride for two purpose (really only one) fitness and for shorter distance errands like grocery shopping every few days (again for fitness purposes). So I don't have to ride in really bad conditions. I wanted a light that was bright enough to see unlit trails at my speed (10-15mph) and that would have a good battery life and quality of build. I ended up trying a couple of different lights and settled on the Cygolite Minty cross 350 which I got for $175. I then ordered a second mounting bracket.

I tend not to like chinese products for a number of reasons.

dscheidt
09-24-10, 09:00 PM
The other problem is that in order to maintain the economy of the thing, you want to use commonly used batteries that are made in the hundreds of thousands. 18650s have GOT to be the most common LiIon cell in the world, by a huge margin, because it's the cell used in laptop computer packs and other things. As soon as you switch to a different cell, you're probably going to double your cost right there.

IN the case of the magicshine, they use commonly used cells. They seem, though, to buy them from people who don't believe in quality control.

znomit
09-24-10, 09:13 PM
IN the case of the magicshine, they use commonly used cells. They seem, though, to buy them from people who don't believe in quality control.

Perhaps they are getting the cells that failed QC? :innocent:

dscheidt
09-24-10, 10:09 PM
Perhaps they are getting the cells that failed QC? :innocent:

In many industries, it's normal to group production into lots, and sample a small fraction of the lot. If too many of the sample fail inspection, the lot is condemned or otherwise disposed of. In some cases, that means selling it a discount. Given the wildly variable quality of the few things I've bought from DX, it wouldn't surprise me that's a very common practice among their suppliers. I'm not opposed to that when it's done above board.

Garfield Cat
09-25-10, 07:06 AM
It would have to be two big batteries. One big battery would only give you 3.6 volts, not 7.2 volts. Then you're back to charging in a serial arrangement and that's actually probably the biggest problem. Two batteries in parallel will be forced to stay in sync with one another, and as long as one isn't vastly worse than the other, probably not a big problem.

The other problem is that in order to maintain the economy of the thing, you want to use commonly used batteries that are made in the hundreds of thousands. 18650s have GOT to be the most common LiIon cell in the world, by a huge margin, because it's the cell used in laptop computer packs and other things. As soon as you switch to a different cell, you're probably going to double your cost right there.

Ok, it sounds to me that what we want out of MagicShine is 4 good batteries with a holder that allows us to pop out each battery for recharging. Then the battery holder is both hooked up in series and in parallel to make it work in unison.

This reminds me of the old days of my Marantz tube amp and preamp. I think it was the 7c and 8b. Everything had to be matched. I bought Telefunken tubes from Germany. Even the 12AX7's.

ItsJustMe
09-25-10, 10:34 AM
Ok, it sounds to me that what we want out of MagicShine is 4 good batteries with a holder that allows us to pop out each battery for recharging. Then the battery holder is both hooked up in series and in parallel to make it work in unison.

That would be ideal. BatterySpace sells 4 x 18650 holders with integrated protection circuitry for $20. Honestly, if you're charging each cell separately, you can get away with using fairly cheap cells, and if one dies, it's easy to replace, so you could use the $4 cells from DX and put together a whole pack for < $40. Of course, then you need a separate charger, but the 2 cell 18650 charger that I bought for about $7 from DX works well. I might buy two of them if the charge wasn't fast enough or just because I'd forget to swap them and get to the end of the day and have only 2 charged cells.

I think if I had it I'd probably still charge the whole pack as a pack maybe 2 out of 3 times, and charge the cells individually 1 out of 3 times. That would equalize the cells frequently without the hassle of removing the cells.

colleen c
09-25-10, 11:46 AM
That would be ideal. BatterySpace sells 4 x 18650 holders with integrated protection circuitry for $20. Honestly, if you're charging each cell separately, you can get away with using fairly cheap cells, and if one dies, it's easy to replace, so you could use the $4 cells from DX and put together a whole pack for < $40. Of course, then you need a separate charger, but the 2 cell 18650 charger that I bought for about $7 from DX works well. I might buy two of them if the charge wasn't fast enough or just because I'd forget to swap them and get to the end of the day and have only 2 charged cells.

I think if I had it I'd probably still charge the whole pack as a pack maybe 2 out of 3 times, and charge the cells individually 1 out of 3 times. That would equalize the cells frequently without the hassle of removing the cells.
My cheap trustfire 18650 outlasted my MS pack most likely because they are individually charge and series charge like the MS pack.

Technology sooner or later will fix these bugs. Currently there is 3000ma 18650, however if they ever can make a 4400ma 18650, then two in series can run a MS with the same volts and runtime. To solve the series charging problem, a balancing charger can be use as an option assuming the pack is wired for that. This probably will allow the battery to last the 2-3 years of useage. Until then, we'll have to grin it and bear it.

I also think a eight pack will be much better than the four pack if the pack will get depleted down to 50% depletion. Not sure if this is a fact, but I think the pack will maintain better balance of the cell if it get recharge at 50% instead of a full drain. So that means I will have to recharge a 8 pack after 3 hours use.

One thing I am looking into is those SST 50 flashlight. They run on a single cell and gives out just as much light as a MS. Only drawback is the 1 hour runtime. I might be hacking into one of those flaslight and add an external pack of 3P1S to get 3 hours of runtime. Since they are not in series, charging and keeping them in sync should be less of an issue. Just a thought.......

dscheidt
09-26-10, 08:24 PM
My cheap trustfire 18650 outlasted my MS pack most likely because they are individually charge and series charge like the MS pack.

Technology sooner or later will fix these bugs.

It's already solved them. It just involves spending money, and the magicshine is all about being cheap. It's perfectly possible (and widely done) to build a charge controller that charges the batteries individually, but it's more expensive, and you really should use cells that are properly matched, which costs money. Maybe if costs of good quality Li-ion cells come down, they'll buy first rate ones. But since there's a big market for cheap over quality, maybe not.

Garfield Cat
09-27-10, 08:49 AM
It's already solved them. It just involves spending money, and the magicshine is all about being cheap. It's perfectly possible (and widely done) to build a charge controller that charges the batteries individually, but it's more expensive, and you really should use cells that are properly matched, which costs money. Maybe if costs of good quality Li-ion cells come down, they'll buy first rate ones. But since there's a big market for cheap over quality, maybe not.

Then why not apply good old fashion American marketing, a-la Sears Roebuck? They could offer, good, better, best. Do you really think Craftsman tools are "best"?

ItsJustMe
09-27-10, 11:12 AM
Then why not apply good old fashion American marketing, a-la Sears Roebuck? They could offer, good, better, best. Do you really think Craftsman tools are "best"?

They're the best that Sears sells...

Richard Cranium
09-27-10, 06:11 PM
Oh yeah, I just did another "test." I ran two MS 900s on MS batteries for the same time frame at the same power at the same time. And then I charged them using identical chargers and charging times.

I monitored the battery voltages and charging rates periodically. Both batteries drained and recharged identically. One battery I have owned for several months and has been drained to "auto shut off" about five times as well hours and hours of short term use. The other battery was being used for the very first time.

So -in my case - I have a battery that has been run over 100 hours and appears to act like a brand new battery. Or I have a brand new battery that acts like it has been run over 100 hours - gee whiz.......

Garfield Cat
09-28-10, 09:48 AM
If you do a little research on the MagicShine light, you will find that its made in an Industrial Zone in Shenzhen, Guangdong. You'll also find that this area also makes batteries.

tarwheel
09-28-10, 10:58 AM
I've been using a Magicshine for about a year. I put it away over the summer with longer daylight hours. When I started using it again a few weeks ago, my light was intermittently going out -- a problem that seemed to arising from the connectors between the light cable and battery cable. I emailed Magicshine, and they sent me a coupon for 50% off a new light unit and/or battery. I decided to replace both the light and the battery since I wasn't sure which connector was faulty, and it wasn't a bad deal for $45. I am glad that I made the switch because the new light unit has 5 settings (high, med, low and two blinkie settings), plus the cable is shorter. The cable on my old unit was ridiculously long and I had to fold it up.

My old unit and battery still work and might be useful to someone if they have the know-how to replace the cable connectors.

tcpasley
09-28-10, 11:08 AM
My old unit and battery still work and might be useful to someone if they have the know-how to replace the cable connectors.

tarwheel - I'd be interested in your old light. Send me a PM if you decide to sell it.

tcpasley

Reduce, Reuse, Rebicycle

ItsJustMe
09-28-10, 12:02 PM
Regarding connectors dying, I find it's worthwhile to put some electrical contact grease on anything that might possibly be exposed to the weather. It used to be that every time I've gotten a new car, I pull off all the electrical connectors and spray contact grease in there. I never had an electrical problem.

These days car makers spray the grease in at the plant.

Also, if you have a faulty connector, you can buy a 1 meter extension cable which has one female and one male connector on it, and replace both of them in 10 minutes with a soldering iron and some electrical tape. DX sells these cables for $3.60 I think. I bought a couple just for spares and so I could put the battery in the bottom of my pannier if I wanted to. I also picked up some spare Y cables also < $4.

Garfield Cat
09-30-10, 08:42 AM
I think the manufacturers in China will make just about anything you want them to make. They can make batteries as good as anyone else, I mean quality and features. In fact, they make certain components for the aerospace industry. Its all about the specifications and the testing afterwards.

With the knowledge right here in this forum, a engineer type with business sense, can actually get something going. The Sears-Roebuck analogy was meant to be a figurative expression of how the American consumer tends to think: good, better, best. If the Geoman organization would venture out this way, their strategic planning, I think it would be even more successful.