DX 18650 Chargers: DSD vs. WF-139

[ynggrsshppr]

I decided to get a proper charger for 18650 lithium ions from DealExtreme but I couldn't decide which to get, the DSD charger or the Ultrafire WF-139. Mind you, I hate starting these kind of threads, but bear with me.

The DSD doesn't have independent channels but the Ultrafire does. However there are reports of the Ultrafire overcharging to over 4.2V. How widespread is this? The DSD is also nearly 50% cheaper than the WF-139.

Up until now I've been using the Nano charger with some ghetto rigged paper clips and rubber bands to charge 18650s since I only use these cells lightly. Help a poor soul out.

 

[LEDite]

ynggrsshppr;

I have several of both types of charger.

I have had no problems with either model.

The UltraFire is the better of the two. Mine shut off @ 4.22 VDC.

Larry Cobb

 

[2xTrinity]

If you're worried about overcharge, I'd get protected cells. Battery Junction sells protected 18650s for around $6 each. Those have built-in overcharge protection and will disconnect themselves if a charger tries to overcharge them.

 

[balazer]

From everything I've read, the DSD does not overcharge cells. It always keeps them below 4.2, usually closer to 4.15. That will extend the life of the cells.

However there are a few reports of the DSD charger failing if you mess with the AC plug connection while it's charging.

If you want independent channels, buy two.

 

[LuxLuthor]

Another option is to get the Pila charger which is best quality of any of these three, and charges each slot independently at 600 mA rate. This is also why we are trying to get a universal cradle setup with better chargers in the other threads here.

 

[JanCPF]

The WF-139 DOES overcharge if cells are left in it - there is no question about it. After the light turns green, it checks the charge status of the cell by sending a small current (in the order of 10 mA) once every other second or so. With enough (several hours) of these small pings of current, the unprotected cell will get overcharged. If however you pull the cell when the light turns green, there is no problems, or you can use protected cells to be on the safe side.

The DSD does not overcharge, but it is slow, and smaller cells like RCR123 will only charge to about 4.07-4.12 volts or so.

Jan

 

[ynggrsshppr]

Balazer, that is such a simple and seemingly obvious answer. I never even thought to buy two DSDs. I think that is what I will do. Thank you.

From what LEDite and Jan says the Ultrafire does overcharge, I think even 4.22V is a bit much.

Lux: A good suggestion but you're talking to a person that hesitates to spend money and has up until now used rubber bands and paper clips to charge 18650s! I'd love to get my hands on a Tenergy charger and a Voltcraft cradle but I can't justify the expense.