Battery charger for mini and full size

[blkhwk07]

Planning on getting the wife a mini and myself a V2 when they get blue in (full size,regular,V2,what do you call it?). Anyway is the pila 4 stage they sell a good charger,I plan on using one charger for both.I've seen some talk of xtar something.We both have Kgo now so we don't have a charger that would work.I'm not looking for the cheapest but more like the best,after I buy two ProVari's no use to skimp on the charger.

 

[markfm]

The Pilas have an excellent reputation. Well built, excellent charging characteristic.

The xtar WP2 II runs about 1/2 the price (around $20 delivered), is a 2-bay 3.7V charger which also has excellent charging profile, only 0.1 mA "trickle", and a 0.5 mA discharge if power is disconnected. The WP2 II also comes with a 12VDC cig lighter adapter for charging in a car. You need an extra pair of spacers (about $1) if you want to charge shorter batteries (I use them with 16340 batteries). With the xtar switch position 1 is 500 mA max current (per bay), for smaller (500 - 1000 mAh) capacity batteries, while position 2 is 1000 mA max output, for 1000+ mAh batteries.

Either is a solid choice. Given the xtar is less than 1/2 the price of the Pila, if it was me I might buy two xtar instead, if you don't already have a charger. Charger failures are pretty rare, but I'm a huge believer in backups.

Since I tend not to be around when I recharge, as an extra safety I power the chargers from a small Belkin outlet timer, $10. Belkin - Conserve Socket Power Timer - White/Lemongrass - F7C009 is what I use (it's available at other places). The timer sits on a power strip outlet, triple tap adapter plugs into the timer, chargers run off the triple tap. The timer is set for 3 hours, I just push the button and walk away. Since the xtar only has a 0.5 mA discharge rate I'm content that even if the batteries sit in the charger for an extended period I'm not losing much runtime.

 

[jkmtwo]

I've had a Pila and it is a fine charger, just not as awesome as my 6 bay Xtar
View attachment 91595

 

[NeonPriest]

what happens if you leave the batteries on the charger even though they are fully charged? my charger doesn't have an auto off so i am just curious as i don't wanna mess my batteries up. any info would be great.

 

[markfm]

It depends on the charger and its charging characteristic. With standard 3.7V nominal lithium batteries, when they are charged you don't want them to go above about 4.2V fresh off the charger. There's a bit of wiggle room, but personally I look at 4.25V as the upper limit I'm happy with, and a little under, say 4.15 - 4.17, is also fine, will extend the life (number of cycles) of the battery though you get a little less run time between charges.

There's a nominal ideal charging characteristic, basically the charger adjusts the voltage and current level as the battery charges. The Pila is at or near this ideal, and the wp2 II is also "close enough".

If the charger doesn't cleanly shut off, keeps pushing mA into the battery, that's potentially bad. Build up too much energy and the battery will vent or do other nasty things -- it can only hold so much energy. A fair number of chargers continue to "trickle charge", outputting a little current to keep the battery topped-off, at or near its ideal maximum. Some chargers keep a watch on the voltage, and if it drops more than, say, 0.1V, they will top it off again.

The Pila is supposed to be solid all around. The xtar has such a tiny trickle that it is a don't-care for practical purposes, it's only about 0.1 mA. Some other chargers have noticeably higher current at the nominal end of charge -- those you need to pay more attention to.

There is also, separately, the potential for the charger to just plain fail. If it does so you might see voltage go high and/or current output to the battery go high. This is rare stuff, but why I use my separate outlet timer. My batteries charge in a bit over 2.5 hours, so a timer that shuts off after 3 hours buys me some extra margin.

When my WP2 hits end of charge the light changes from red to green -- the charger itself doesn't turn off, but drops to that really low trickle level.

Charging Lithium-Ion Batteries

 

[jkmtwo]

Neonpriest- it depends on the battery, if its a protected battery I don't think it should be an issue.

IMRs are a different story. If you want a good 2 bay charger there is no sense in getting a $10-$15 trust fire, Xtar makes a good 2 bay charger for about the same price
Xtar MP2 II

 

[markfm]

jkmtwo's right -- if you have a protected battery which goes open-circuit at, say, 4.25V, that should work, though I'd prefer to not rely on tripping a battery safety to stop charging due to a charger that isn't shutting down well.

 

[NeonPriest]

wow i never knew any of that, i just thought that nothing happens. thanks so much for the info, i love to learn something new!

 

[jkmtwo]

jkmtwo's right -- if you have a protected battery which goes open-circuit at, say, 4.25V, that should work, though I'd prefer to not rely on tripping a battery safety to stop charging due to a charger that isn't shutting down well.

Exactly, and all it takes is that one time and bad things happen. In this case redundancy is our friend.

But as always, batteries fail, they have before, they will again, if you've never had one fail, like me, don't let that fool you into a false sense of complacency. The best charger is not going to keep you safe. You will keep you safe. Educate yourself.

I'm no expert myself, but I try to keep myself educated on batteries as best I can. You should do the same.

 

[blkhwk07]

Thank you markfm & jkmtwo, so if I'm reading this correctly. The pila might be a touch better,but not worth double the price. Like your point markfm about getting two and having a backup,I have back ups of back ups now. (would hate to have dead battery and no way to charge) Another question I have (think I know the answer) if you have two different size batteries in each bay is each charged and finished separately.(each bay independent)? Thanks for the link to the Xtar jkmtwo,never purchased from them are they reputable?

 

[donnah]

I bought my xtar on ebay...$18 shipped.

 

[jkmtwo]

RTD is solid, I have had nothing but good service with them, Super T, also carries the charger, I think its about the same price. As for different sized batts, I do it all the time, its not an issue, the issue is when you try to charge different battery chemistries, so i never charge a Li-ion and a Li-mn in the same charger at the same time. Though, and I could be wrong here, and you should check up on this, that the Xtar 2 bay is 2 I dependant channels, meaning you can charge 2 different chemistries at the same time, that said even if i knew this for a fact, I still wouldn't do it myself, I'm just not comfortable doing so, so i wouldn't.

As far as Pila and Xtar go, I wouldn't say a Pila isn't worth the price because the Xtar is nearly as good for half the price, I would say the differences between them is so miniscule that the Pila doesn't warrant the price tag, there is virtually no discernable difference between the 2, some may find a technical difference that you and i will never know, fact is, the flashlight community knows more about this stuff than you and me ever will, and they are, from everything I have seen, pushing the Xtar, when people of experience and knowledge speak out, I tend to listen.

 

[blkhwk07]

Thanks jkmtwo, didn;t know about Super T either.Their site says the xtar has independent channels. Think I might pick up a couple of these. Plus gives free car charger,(if the Provaris ever leave the house).