stringbreaker

I ordered the new Magicshine replacement battery. The runtime with a full charge hooked up to my tail light and headlight was pretty dismal. I normally got 3 mornings from my old battery and using the new one this morning the light on the back of the headlight indicating the battery getting low was on after only riding for 37 minutes. I was running it on the high beam but that's how I ran the other light and it would go 3 mornings with out recharging. NOT IMPRESSED.

colleen c

Have you tried to run it till the light cuts out automactically? There was another customer over at MTB forum who also had his red light came on sooner with the new pack. He was advice to ignore the red light. I sort of question that advice because the original design of the light head was suppose to be design such that the red indicator is a warning telling us that the battery is going to shutoff soon. If the new pack design cannot match the original intended design of the light head, then that warning light is good for nothing.

So far, I'm not impressed with new pack either. The case is very nice. The battery or PCB is iffy. I got a new 900 light set last week with the GMG battery. I plugged in charger. Green light showed right away. I tried battery on the light and nada. Took an old light and still nada on new battery. Took new light on old battery and light head is OK. Tried the new charger on old battery and charger is OK. Battery came DOA! Send pack back to Geoman under warranty. Should be getting back one this or early next week. ARGH!!!!

Richard Cranium

As near I could tell, the light heads led colors change as a result of voltage. This of course is conjunction with whatever current is being supplied. Running two lights will always change the "indicator light" values.

I believe the old batteries were 2100mA cells and the new ones are 2250mA. This equals 3Ah increase in capacity, 42 to 45, in theory about 30 minutes more run time on high, but using two lights perhaps 20 or less.

And remember, additional capacity will not raise voltage, only prolong current draw, so the "low power red" light would be on longer.

Since my first recall letter was "rejected" by the post office - it remains to be seen when and if my second will make it - probably should have sent it registered mail. Luckily I still use Dinotte. And now I can open them and replace cells as needed.

chipcom 

I did the paperwork to replace my battery, but haven't taken the old one down to recycle yet. I'm watching your experiences with this new battery before I commit, since the old battery has been problem-free for me.

RT

Like Chip, I still use my old battery with great results. I had another older battery that died after warranty, creating the need to buy another battery, so I had a spare - this one is what Home Depot got as it was also on the recall list. I'll run a test between the two when the new one arrives.

stringbreaker

I find it odd that the GMG site states the light should run 9 hours on low and 3 hrs on high so even if I'm running a tail light and headlight I should have more left power left. I'm running the old light just with the new battery pack. the green light was on for about 30 minutes of my ride and the last 5 or so it turned red. I wouldn't want to try to get even two mornings of riding which would amount to just over an hour without recharging the battery pack. Think I will contact GMG and see what they have to say about it.

ItsJustMe

The red light on my MagicShine is utterly useless. I've had it come on after 30 minutes and the light continues to run for 2 hours, or I've had it stay green until 5 minutes before the battery died.

The new ones are probably better, mine was one of the first. I don't pay any attention to the stupid thing, I just charge it every 3 or 4 days.

stringbreaker

I'll see if I can get two days out of it. I recharged the pack this afternoon and it charged up in about an hour and a half. Another thought, I used the original charger and I'm wondering if I need to buy a new charger too?

Richard Cranium

There is some variation on how chargers work. I have chargers from Dealx, Geo, and Dinotte and they all have slightly differing cut-off voltages. (green light level)

Typically all chargers, continue to pass current to batteries for nearly three hours after the green light comes on. But understand this. The current levels are down to 200mA or less, and this means that the last "three hours" of charging only add 7-15 minutes of "high run time" or perhaps nearly an hour on low run time.

Again, I'll say it, anyone that has access to two accurate multi-meters can be an expert at this stuff and know quite quickly if a battery or charger is defective. I've had chances to "see" how good batteries and chargers work.

Oh yeah, one other thing - "normal users" can have bad results because of bad connections during charging. Everyone should take special care to plug together cables and "twist" or rub contacts together, otherwise charging might not work correctly, in other words "false green lights."

RT

I don't know how this might apply in the world of lighting, but my HTC Incredible retains a charge much longer when I charge it, disconnect it, then 'bump' charge it again for about ten minutes. Under normal charging circumstances, I've never had an issue with run time. When I first received the new battery (not the recall replacement, but my original replacement), I ran a test on high, and it lasted 3 hours and 28 minutes before dying out completely. This is with the charger that came from GMG.

rumrunn6

cr*p! shuda kept my old battery (which was awesome) ... dam ...

Richard Cranium

No too sure you really "bump" the battery's charge.

Many cell battery/charger circuits have dedicated set of "charge terminals" that are controlled by a chip to assure no chance of over charge. In other words, when cell phones being charged with the battery inside the phone, once the "charge indicator" reads full, or turns green, or whatever, the charging is completely stopped.

You can check for this feature by looking at the cell phone battery. If there are more than three copper terminals showing at the end of the battery, the phone shuts off charging when "full level" indicator is on.

No such thing as "trickle charge" for phone-batteries with these kinds of circuits. "Smart phone batteries" have four or five terminals.

RT

All I know is that if I do not bump it, I go from 100% to 90% in about an hour. Under the same circumstances, a bump at least doubles the time it takes to lose 10%. I don't profess to know the science behind it, just practical experience. Not sure if it translates into the MS issue.

ItsJustMe

Keep in mind that you don't really know the battery's actual capacity until you've sent it through a few full cycles. Whatever the chemical reasons behind it, it seems that you need to "wake up" new batteries sometimes.

kuan

I've heard that too but what I want to know is why.

davidad

https://batteryuniversity.com/learn/a...rime_batteries

stringbreaker

I charged the battery again last evening and this morning the red light comes on about half way through my commute. Not sure how this is gonna play out but I'm wondering if this thing is going to be unreliable. I think I'll run the light and discharge the battery all the way and see what I get then.

socalrider

I'm still getting good runtimes on my 1st gen battery.. Has anyone tried this model battery: Magicshine MJ-828 Upgrade Battery

https://bikeempowerment.com/Magicshine.html

stringbreaker

I have not seen this. Geomangear doesn't sell that one.

Richard Cranium

I can't account for what someone else may experience. However, most of my comments are born out actual measuring of batteries, lights and chargers.

On guy here says he can't tell how many terminals his cell phone battery has - but professes knowledge of sophisticated undocumented battery charging techniques. I kind say of hmm,, really?

For anyone, if you want to complain about run time of a battery, then at least get a mulit-meter, learn how to use it and measure you battery after charging and after usage. Simply, looking at indicator lights, whether they are on a charger or a battery is worthless.

If I did not have a meter, I would always let my battery charge over night, or at least six hours. I would always twist the connectors and make completely sure the battery and charger are connected. I would use a stop watch on my wrist watch to count run time of the battery, and know for sure which mode the light was in.

I've got Lithium Ion batteries that show almost no loss after two years - more than 200 hours of operation. But I have been given "bad" batteries to test and know what happens to their terminal voltage at rest and it is easy to spot a bad battery with a meter.

The only actual question anyone could ask is: Do I have a bad battery or a bad charger?

rscamp

Ask a friend with a hobby charger to charge and measure the capacity on discharge. Then you know...

RT

WTF, Dick? Yeah, really. If you re-read my post, you will note that I never claimed not to know how many terminals my cell phone battery has. Also, plug 'cell battery bump charge' into the mighty Google, and there are many, many articles on the effectiveness of this technique.

No need to get snobby about it, man. Do your homework before calling someone out like that.

rscamp

Depending on the quality of the charger and the method it uses for terminating the charge, it can increase the state of charge to "bump" charge as you describe it. So you are not crazy! If doing this results in a big change in SOC, however, it is generally an indication of a poor quality charger.

I would also add that using a voltmeter is not sufficient to measure the capacity or 'health' of a battery. A tool is required that can measure capacity to a terminal voltage for a given discharge rate. Ideally, the tool can also provide an indication of internal impedance which is generally higher for poor quality or high-capacity cells and increases as the cells age.

In other words, see post #21.

Richard Cranium

Well, well, thanks for the education.

However, my comments stand for they what they are - and that is - many cell phone charging, or maybe only "some" cell phone charging systems will cut voltage to the battery through a circuit, which I assume makes "plug and bump useless."

I will heed your expert directive and investigate whatever bump charging means to cell phone users. I can state with some authority it will not work on the several models of Samsung and LG phones I own. But I also admit I own cheaper models of phones, much different from yours.

stringbreaker

AWWW s*&t all I wanted was some info on the new battery from those that had the replacement battery and to inform how mine was or was not performing. I'm not a Frappin battery expert, I don't even play one on TV, I'm like most people I charge the thing and use it till it needs charged again expecting the manufacturer would be able up front about their runtimes in the real world. I would think MagicShine would inform anyone getting the replacement battery if there were going to be issues with the original headlamp unit and the supposed runtimes.