Why wireless?

[crazyhorse]

I am worried about these Trustfire and Ultrafire batteries period. The quality control seems to be very lax. I bought 4 Trustfire protected 14500 and one came in DOA. It looks like the protection circuit failed resulting in an open circuit. I bought 6 Ultrafire 14500's and one of them is intermittantly open on the protection circuit. What are the chances that one will fail due to a short?

I'm certainly not impressed with the design so far.

Kevin

I'm too dumb to worry about things like that. When I get up in the morning and find a big, smoking hole blasted in the granite counter where the charger lives, I'll start worrying

I have Trustfire 14500. 1 of 10 was DOA. Completely dead and wouldn't take a charge if left on the charger for eternity. Would that be a bad PCB?

 

[a2dcovert]

I have Trustfire 14500. 1 of 10 was DOA. Completely dead and wouldn't take a charge if left on the charger for eternity. Would that be a bad PCB?

I guess it's the PCB going bad. Usually even a dead battery should have some voltage.


Kevin

 

[me5647]

Perhaps these doa batteries were stored for along time before they shipped out and the voltage dropped below the low voltage protection cut off, so they cant be charged with a normal charger.

I know li-ion is supposed to hold a charge for a long time but since you both got 1 dead one in a multi pack maybe they send you all good ones and throw in one that they know is dead? idunno makes me wonder

 

[me5647]

"Lithium-ion is charged with approximate 4.2 ± 0.05 V/cell except for military long life that uses 3.92 V to extend battery life. Most protection circuits cuts off if either >4.3 V or 90 °C is reached. Also if threshold of below 2.50 V/cell is reached the battery protection circuit may render it unchargeable with regular charging equipment. Most battery protection circuits stop at 2.7-3.0 V/cell."

What kind of voltage do most of them have when you get them?

I believe once they drop so low they can no longer power the PCB so it would show 0v on the normal battery contacts, unless you were to disassemble it and measure directly on the cell.

 

[a2dcovert]

I'm going to cut the shrink wrap off of one of them and see if I can determine where the problem is. If I have to I can replace the PCB, I plan on buying a few of them with my next order.

 

[warp1900]

I have had a couple of 14500 (protected) go to 0 and when recharged it only goes up to anywhere between 0.3 to 2.3v.

I place them in my charger again, (even when the light is showing green) and leave them there for the night and next day they are back to 4.25v.

My charger is nothing special, just an average TrustFire multi size 3.7 charger from DX.


weird huh?


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[a2dcovert]

Yes, that's weird...

I dug into the first trustfire 14500 that arrived DOA. The voltage is 0 volts and the resistance across the battery is completely open. I removed the outer plastic cover and connected the volt meter bypassing the PCB and I have a normal battery. So the PCB is bad as I suspected. I can just replace the PCB and have a working protected battery.

I wonder why the Chinese are the only ones constructing protected batteries in this manner?

Kevin

 

[warp1900]

Yes, that's weird...

I dug into the first trustfire 14500 that arrived DOA. The voltage is 0 volts and the resistance across the battery is completely open. I removed the outer plastic cover and connected the volt meter bypassing the PCB and I have a normal battery. So the PCB is bad as I suspected. I can just replace the PCB and have a working protected battery.

I wonder why the Chinese are the only ones constructing protected batteries in this manner?

Kevin

I guess what happens when I put it back on my charger is that somehow it "bumps" the protection circuit and gets it to work again?

I noticed that those batteries seem to end up with 0 readings frequently after vaping with them several times and I have to put them through the whole "double charge" process again to get them to work.



Maybe because they are the only ones manufacturing Li-ions ?
And most every other thing.



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