Test/Review of Charger Xtar SV2 Rocket

[vadimax]

I guess, those cells aren't that expensive that you decide to either be hit with a shrapnel or put your house on fire

Personally for me it was enough of more than normal heating and chemical odor to dump a cell. Well, there was a headache as well to be true. That chemical smell was poisonous I guess.

 

[TinderBox (UK)]

Question can each channel be set to a different charge rate, say 250ma for an AAA nimh and 2000mah for an 3400mah 18650 or do both channels have to be the same rate??

thanks

John.

 

[HKJ]

Question can each channel be set to a different charge rate, say 250ma for an AAA nimh and 2000mah for an 3400mah 18650 or do both channels have to be the same rate??

No, both channels use same charge rate.

 

[TinderBox (UK)]

No, both channels use same charge rate.

Thanks Henrik, saved me again.

John.

 

[david57strat]

I am using this charger exclusively now.
About 2 months ago the spring broke on one of the sliders.
Rather than go to the hassle of returning the thing for a new one I decided to fix it.
Removed rubber feet,unscrewed the bottom and revealed the problem.
The little plastic post the spring fixes to broke.(this plastic post is way underdesigned flimsy very poor)
I was able to drill a hole in the PC board just behind the broken post and attached the spring in the hole.
Better than new.
Just my 2 cents

The same thing happened to me, after about six months of daily use of that charger (I had two of them), and on two separate occasions (both times, with a 26650 battery in the well).

The first time, I just went into the store, with the charger, in all of the original packaging, and they immediately exchanged it, no questions asked.

The second time (maybe with the other unit..who knows), they were out out of stock, but set me up with a loaner charger, apologized for the problems, said they would advise XTAR of the problem; and a few weeks later, I had the replacement unit (Which I also picked up at the store, when they still had a storefront to go to lol.

These guys have always taken care of me, so I've never had any reservations about buying XTAR chargers.

Now, I'm enjoying four of these babies - among others

 

[joelbnyc]

Just wanted to give a big thanks to HKJ for taking the time to purchase lab equipment to make all these charger and battery measurements, and presenting the data in such a hugely useful format: the battery comparator and sortable round cell charger table. Such an immense un-remunerated contribution shows quite a passion and is much appreciated.

Thinking of picking this charger up as a non-pulse-charging backup/complement to my Opus 3100, esp at cyber-week sale price. I have had a few older Xtars without displays.

I don't fully understand the difference between simulated cc/cv (is this what pulse charging is?) and actual cc/cv, but I take it this charger does not use the pulse charging that was noted as a possible downside to the Opus?

 

[Gauss163]

I don't fully understand the difference between simulated cc/cv (is this what pulse charging is?) and actual cc/cv, but I take it this charger does not use the pulse charging that was noted as a possible downside to the Opus?

The OPUS "pulse" charging works fine for 99.999% of consumer applications. There are no scientifically backed studies that prove otherwise - only old-wives tales that have no scientific basis.

 

[HKJ]

The OPUS "pulse" charging is works fine for 99.999% of consumer applications. There are no scientifically backed studies that prove otherwise - only old-wives tales that have no scientific basis.

I do not believe that you have yet shown a study that shows it is fine to charge a battery with 10 times rated charge current (The Opus do that with 10440 batteries).

Simulated CC/CV is not about the current, but because the charge algorithm is CC and current is adjusted depending on battery voltage with current off, this is not the same as CC/CV, but may look similar in many cases. The difference will often show up with old batteries, where the simulated CC/CV may go above 4.2V

 

[Gauss163]

I do not believe that you have yet shown a study that shows it is fine to charge a battery with 10 times rated charge current (The Opus do that with 10440 batteries).

Extremely tiny Li-ion cells that may possibly be more quickly degraded by the Opus are rarely used by consumers. That's why I said 99.999%

Simulated CC/CV is not about the current, but because the charge algorithm is CC and current is adjusted depending on battery voltage with current off, this is not the same as CC/CV, but may look similar in many cases. The difference will often show up with old batteries, where the simulated CC/CV may go above 4.2V

It's not clear what you are trying to say. How does that have anything to do with the Opus? [EDIT: Ah, the above seems to be a reply to the OP's earlier question, not to my comment on the Opus. It would be better to reply directly to the OP so as not to cause further confusion between the Opus charge algorithm and others].

 

[HKJ]

Extremely tiny Li-ion cells that may possibly be more quickly degraded by the Opus are rarely used by consumers. That's why I said 99.999%

10440 is not extremely tiny, AA sized flashlight are popular and some of them uses LiIon.
16340/14500 is also charged with a rather high current, compared to their rating.

It's not clear what you are trying to say. How does that have anything to do with the Opus? [EDIT: Ah, the above seems to be a reply to the OP's earlier question, not to my comment on the Opus]

Opus uses simulated CC/CV, that is easy to see when it is charging old cells.

 

[Gauss163]

Opus uses simulated CC/CV, that is easy to see when it is charging old cells

"simulated cc/cv" is not standard terminology, so it wasn't clear what you meant. I thought you were referring to some of the more recent algorithms which dynamically adjust the charge current.

10440 is not extremely tiny, AA sized flashlight are popular and some of them uses LiIon ...

Such small Li-ion cells are (relatively) rarely used by consumers so I think they fall into the 0.001% category in general consumer usage.

Furthermore, I am not aware of any scientific studies proving that the Opus algorithm will cause (significant) degradation even for those smaller cells. It makes no sense to attempt to apply parameters from pure CC/CV algorithms to other variants such as that used by Opus. There can be dramatic differences in cell behavior under pulsed vs. constant current cases, so completely separate analyses need to be applied to obtain meaningful results. Even experts on Li-ion electrochemistry have made wrong guesses on related matters.

 

[joelbnyc]

Oops, didn't mean to set off this little spat again.

I do charge 350mAh 10440 frequently, for my keychain light. I'd previously been using the Xtar XP1 Hummingbird at 0.25A for 10440 and 14500, so I will stop using the Opus 3100 for these small cells then.

Edit, looking at the curves, I may go with the Enova Gyrfalcon all-44 for a "pure" cc/cv simple charger (one of these days I will get a SkyRC 3000), because of 0.1A min and curves look to terminate right about 4.19V for 18650:

Whereas my Xtar WP2 II charges 18650 to ~4.15V and this SV2 Rocket seems to reach ~4.22-4.25V during charging, though perhaps this will have a negligible effect on lifecycle?

 

[Bullzeyebill]

Oops, didn't mean to set off this little spat at again.

Yes, it is happening again. Good if it could be done via PM's. Speaking as a mod.

Bill

 

[HKJ]

Edit, looking at the curves, I may go with the Enova Gyrfalcon all-44 for a "pure" cc/cv simple charger (one of these days I will get a SkyRC 3000), because of 0.1A min and curves look to terminate right about 4.19V for 18650:


Whereas my Xtar WP2 II charges 18650 to ~4.15V and this SV2 Rocket seems to reach ~4.22-4.25V during charging, though perhaps this will have a negligible effect on lifecycle?

The actual charge voltage may vary between copies of the same charger, i.e. do not base you decision on that.
Higher voltage when charging is finished means more energy in the battery and it will also lower the lifetime a bit.

 

[start90a]

Incredibly many thanks to HKJ for his tests.
The Optus pulse charge of 1 time at 2.2 A and 10 times at 0 A although there's no study to tell with no doubt isn't good for cell's life, common sense would say that a cell rated of little capacity should avoid useless charging patterns.
I prefer a co stand charge of 0.25 A instead of that loop.

 

[TinderBox (UK)]

I want to run two of these charger`s side by side, Does anybody know if it will run without damage on a 15v 5a power supply, It does come with a car lighter socket adaptor and the voltage from a car lighter socket can be quite high with the engine running.

I have a splitter cable on order to power both charger from the same power supply.

The power supply is from an old SkyRC MC3000 the only part i kept when it died.

EDIT: I decided to order an 12v 5a power brick for £11.66, Better safe than sorry.

Thanks

John.

 

[xxo]

And, by the way, I decided to use the authority of the CPF for the evil cause



I am a CandlePowerForums member and there are a couple of issues detected with the SV2 model:


1. When there is a power outage the charger has no memory and defaults to 1A charging that is absolutely no good for small batteries.


2. Sliders' internal spring connect points are too weak and tend to snap broken. As a result people have to open a charger and drill new connect points in the electric board:


Click here to view the original image of 850x850px.

Would you be so kind as to address these problems in the upcoming SV4 model?


Yours faithfully, Vadim.

I've had two SV2 rockets break like that, all four spring posts - it's a shame that the construction is so poor.

 

[TinderBox (UK)]

I opened my new Rocket`s and they use PCB REV A-3 but they still use the plastic poles that the spring clip around, The poles then enter holes in the back cover when it`s fitted so there fixed at both ends.

I took some photo`s if they are of use.

John.

 

[asleep]

I've had two SV2 rockets break like that, all four spring posts - it's a shame that the construction is so poor.

Three broke for me, and I use them very infrequently.

Only reason I got three was at time of purchase it was ~$5 more to order three with free shipping than one and paying for shipping. Looking for something more durable now.