UltraFire 18650s?

[kramer5150]

oops thanks for the correction

 

[Arnulf]

X2 cells, 4800mAH/350mA

The DSD, while like you say, a CC only charge method, from the testing I have done, the way it works is to run CC till 4.25V charging voltage is reached (roughly), at which point it terminates, which can result in a resting cell voltage anywhere from ~4.12-4.22V depending on the capacity and the internal resistance of the cell. Installing cells in pairs will result in higher final termination voltages. moving up to the higher power wall-warts (NOKIA) results in lower final resting voltages (higher charge rates result in a larger differential between charging and resting voltages).

4.25V is within the parameters set by almost all li-ion cell manufactures and is a perfectly safe charging voltage IMO. Provided the resulting charge is close to 4.20V or less it's pretty decent.

To prevent termination voltages in excess of 4.20V on larger capacity cells, the best thing to do is charge 1 cell at a time.

Eric

You got a link to the wall mart charger?

 

[Arnulf]

This sucks...them fluke DMM are too expensive.

 

[brted]

You can get one of these from Amazon. It is cheap and it works, and it measures amps as well as volts. Your charger is okay, but you need to measure the voltage. What if one of the batteries is dead and not taking a charge and the other gets a full charge and you stick them both in a light?

http://www.amazon.com/dp/B001T3Y8XW/?tag=cpf0b6-20

 

[Arnulf]

You can get one of these from Amazon. It is cheap and it works, and it measures amps as well as volts. Your charger is okay, but you need to measure the voltage. What if one of the batteries is dead and not taking a charge and the other gets a full charge and you stick them both in a light?

http://www.amazon.com/dp/B001T3Y8XW/?tag=cpf0b6-20

I bought this DMM local a few hrs ago...I was worried that I had over charged my 18650s.....a few pics.

 

[march.brown]

It looks to me as though the switch should be at the two o clock position ... 20 Volts ... You might be on a battery test position where it puts a load on the cell .. It shows 1.5V , 9V and 12 V , in the area that the switch is shown in the picture.

Did you read the instructions ?

These cells need to be measured open circuit.
.

 

[Arnulf]

It looks to me as though the switch should be at the two o clock position ... 20 Volts ... You might be on a battery test position where it puts a load on the cell .. It shows 1.5V , 9V and 12 V , in the area that the switch is shown in the picture.

Did you read the instructions ?

These cells need to be measured open circuit.
.

Yeah....it said that its the position for checking batteries?

 

[brted]

Looks like a good meter for you. You'll enjoy having it. I agree it is in on some kind of battery test mode and should be switched to the 20V selection.

 

[Arnulf]

Looks like a good meter for you. You'll enjoy having it. I agree it is in on some kind of battery test mode and should be switched to the 20V selection.

Yeah....I am glad I bought it.
Yeah....you fellas are right....I changed it to 20....they are both charged to 4.02 volt that is good enough isn't it?

 

[Bullzeyebill]

Should be closer to 4.2 volts. Doesn't have to be exactly 4.2 volts. 4.12-4.20 would be good. That 12 volt battery check position had a healthy load applied to the 18650, maybe pulled it down some.

Bill

 

[Arnulf]

Should be closer to 4.2 volts. Doesn't have to be exactly 4.2 volts. 4.12-4.20 would be good. That 12 volt battery check position had a healthy load applied to the 18650, maybe pulled it down some.

Bill

Thanks Bill

 

[mdocod]

You got a link to the wall mart charger?

wart, not mart

Check the used electronics supply house or garage sales or anyone doing an old cell phone drive and ask to dig up a charger.

Eric

PS: The instructions for your multimeter that are telling you to use the battery test functions of the meter are assuming a 1.5V alkaline, or a 9V alkaline, or a 12V lead acid more than likely. Using any of those settings for a 3.7V li-ion cell will not generate any meaningful information.

 

[Arnulf]

wart, not mart

Check the used electronics supply house or garage sales or anyone doing an old cell phone drive and ask to dig up a charger.

Eric

PS: The instructions for your multimeter that are telling you to use the battery test functions of the meter are assuming a 1.5V alkaline, or a 9V alkaline, or a 12V lead acid more than likely. Using any of those settings for a 3.7V li-ion cell will not generate any meaningful information.

The DSD charger light turned green at 4.20 volts. :thumbsup:

 

[march.brown]

The DSD charger light turned green at 4.20 volts. :thumbsup:

.
Magic .

.

 

[Arnulf]

Yeah....I think it works more efficiently charging 1 battery at a time.....and thanks to the DMM I have peace of mind that it is charging correctly.