Review of / Measurement on Soshine SC-S7 Charger

[kosPap]

Sorry.....The charger shows a difference of 0.13-0.16+ volts.
My DMM is accurate cos it reads correctly expected voltages in all other cases.

I just measured a battery (using 2 DMMs) at 4.01V.
The charger shows it at 4.2V and 90% full.
it will keep charging it untill it shows 100% full.
The DMM will show the battery then at 4.17-4.18V fresh of the charger

 

[schizeckinosy]

I have a feeling that there is a little dial in the charger so that it always reads 4.2v at termination no matter what it is actually doing!

[edit] I just reviewed the review charts more carefully and they indicate 0.05v less charge on usb. I am using USB because that will be my preferred method to use this - my "travel" charger. I will plug it in to the wall today and see what it does.

 

[kosPap]

BTW my charger came from the same retailer as HKJ's but mien is a bit different.
Came in a cbe like cradboard box, and the dispaly screen is Green, not orange...

 

[Norm]

I have a feeling that there is a little dial in the charger so that it always reads 4.2v at termination no matter what it is actually doing!

4.2V is the V that the charger should apply to the battery, you are seeing the V applied by the charger, there is no way of reading the battery V whilst the charger is charging.

The charging algorithm is CC/CV see the red line in HJK's first graph, where it shows 4.2 V in the final stage of charging.

Norm

 

[kosPap]

aha! and damn!

I thought it woudl show actual batery voltage and that was one of the buying resons....

 

[HKJ]

aha! and damn!

I thought it woudl show actual batery voltage and that was one of the buying resons....

My guess is that it shows the real battery voltage, i.e. measures voltage when the charge current is turned off. Due to the small difference (About 0.1 volt), I do usual not check if this is the case.
But this voltage will drop significantly, when the charge is finished (The voltage is not the same after 0.1 seconds rest as after 10 seconds rest or 10 minutes rest).

 

[schizeckinosy]

My charger seems to read only about .03v higher under charge. Norm and HKJ, I understand that what you described is correct behavior - I have been reporting the ~10sec resting voltage, but the charging voltage is also significantly under 4.2. Mine has a green display as well.

I charged a cell with the AC adapter, and the final v was 4.14 - consistent with the above charts it was higher than with USB, but still a bit low. All in all, I'm pretty happy with the performance so far, and if the cheezy case ever breaks, I'll probably shrink wrap the guts and use magnet leads for an even smaller package!

 

[kosPap]

I did just a simple test....Put the leads of the DMM on the battery when charging....The screen showed 4.0 volts, the DMM was reading a fluctuating voltage between 3.4 & 3.9 volts. I immediately disconnected the power and the battery showed 3.86 volts.
thanks Norm!

 

[Perfectionist]

The charger has many interesting features: Charges both LiIon and NiMH, shows charged capacity, detect bad batteries, shows charge state for LiIon.
But all these features are only interesting, if the charger does a good job. It looks like it does a good job on NiMH and an acceptable job on LiIon, but I am not impressed with the pulsing when the charge is supposed to be finished. The discharge of a few mA is not really significant, except if leaving the batteries in the charger for days.

Great Review!

You say it only does an "acceptable job" on LiIon - what harm does the pulsing do to the battery? If a battery is kept in the charger for a days or even weeks, would it eventually kill the cell?

Is the Xtar XP1 a better charger that this, even though it doesn't fit 18650's?

 

[HKJ]

You say it only does an "acceptable job" on LiIon - what harm does the pulsing do to the battery? If a battery is kept in the charger for a days or even weeks, would it eventually kill the cell?

Yes, maybe not in an hour or a day, but it will kill it much faster than correct charging. As long as you remove the battery within a few hours of charge termination I do not believe that the charge will damage the battery.
I have not tested it, but everything I have read says that LiIon does not tolerate over charge or trickle charge.

Is the Xtar XP1 a better charger that this, even though it doesn't fit 18650's?

That depends on what you are using the charger for and how. The slow termination of XP1 on NiMH when used at 0.25A is not exactly a good idea, but it does a very good job on LiIon.

 

[Perfectionist]

Yes, maybe not in an hour or a day, but it will kill it much faster than correct charging. As long as you remove the battery within a few hours of charge termination I do not believe that the charge will damage the battery.
I have not tested it, but everything I have read says that LiIon does not tolerate over charge or trickle charge.

I see, so if I remove the battery as soon as it is charged, would you consider the Soshine to be a good charger otherwise?

Also, why did they make it pulse if it's not good for the battery? Are Soshine planning on relaseing a new model with this problem remedied?

That depends on what you are using the charger for and how. The slow termination of XP1 on NiMH when used at 0.25A is not exactly a good idea, but it does a very good job on LiIon.

So I should only use 0.24A on LiIon? If I use 0.50A on NiMH would it solve the termination problem?

Do you know if Xtar will release another version which is big enough for 18650 batteries?

 

[HKJ]

I see, so if I remove the battery as soon as it is charged, would you consider the Soshine to be a good charger otherwise?

Fairly good.

Also, why did they make it pulse if it's not good for the battery? Are Soshine planning on relaseing a new model with this problem remedied?

Pulsing usually makes it possible to measure the voltage without any current, i.e. battery and connection resistance is not significant.

So I should only use 0.24A on LiIon? If I use 0.50A on NiMH would it solve the termination problem?

There is not reason to charge with a extra low current for LiIon.
With NiMH on the XP1 it is best to charge at 0.5A, this makes the termination much more reliable, but not perfect.

Do you know if Xtar will release another version which is big enough for 18650 batteries?

Do you mean the XP4?

 

[Perfectionist]

Fairly good.

What charger (with a similar form factor) do you think is excellent and would recommend?

Pulsing usually makes it possible to measure the voltage without any current, i.e. battery and connection resistance is not significant.

So why did they make it keep pulsing after the battery is fully charged?

There is not reason to charge with a extra low current for LiIon.
With NiMH on the XP1 it is best to charge at 0.5A, this makes the termination much more reliable, but not perfect.

So it's best to keep it set to 0.5A for all batteries, except LiIon 10440's?

If the termination is still not perfect, would it cause any damage or danger?

Do you mean the XP4?

I mean a brand new product - is there a reason why Xtar didn't make the XP1 big enough to take 18650's? Seems very silly to me!

 

[HKJ]

What charger (with a similar form factor) do you think is excellent and would recommend?

The ML102 is a good charger.

So why did they make it keep pulsing after the battery is fully charged?

No idea why the did it for LiIon. For NiMH it is for the trickle charging.

So it's best to keep it set to 0.5A for all batteries, except LiIon 10440's?

For 16340 there might be a slight advantage of 0.25A charge.

If the termination is still not perfect, would it cause any damage or danger?

NiMH is not really a dangerous battery type, but over charge might reduce the lifetime of the battery.

I mean a brand new product - is there a reason why Xtar didn't make the XP1 big enough to take 18650's? Seems very silly to me!

Xtar has a line of chargers, the XP1 is a small lightweight transportable charger, they have other chargers for 18650.

 

[Perfectionist]

The ML102 is a good charger.

You mean these?

http://www.fasttech.com/products/0/...er-ml-102-universal-usb-smart-charger-version

http://www.fasttech.com/products/0/...r-ml-102-universal-usb-smart-charger-version-

I take it that the Version 5 is the best one to buy?

 

[HKJ]

You mean these?

http://www.fasttech.com/products/0/...er-ml-102-universal-usb-smart-charger-version

http://www.fasttech.com/products/0/...r-ml-102-universal-usb-smart-charger-version-

I take it that the Version 5 is the best one to buy?

I have only tested the one with the spring, the other one is limited more limited in what length batteries it can handle.

 

[Perfectionist]

I have only tested the one with the spring, the other one is limited more limited in what length batteries it can handle.

Is the circuitry the same in both?

 

[HKJ]

Is the circuitry the same in both?

Because I have not tested the new version, I cannot say anything about it.

 

[Perfectionist]

Because I have not tested the new version, I cannot say anything about it.

I'll get the older version you've tested then. Thank you very much for your help dude, you da man!

 

[Perfectionist]

Hello again HKJ - what is your opinion on the Xtar WP2S? Is it better than the SC-S7 and ML102?