A few li-ion questions

[rumm]

I've been using 14500's for a variety of things and I just want to make sure I have the right information on a few things.

I currently have some tenergy 14500 unprotected and AW14500 protected.

1. The charger is use is a tenergy TR-001. I can't seem to find any info on it. Does anybody know if this a smart charger? If I leave the unprotected batteries on it to charge while I sleep will I face any sort of danger doing this?

2. Using this same charger and the AW protected, it should be fine if I leave them on the charger overnight even if it's not a smart charger, am I right in assuming this?

3. When people talk about over discharging a battery, do they mean letting it die completely or using it in a device that drains it too fast?

4. I read that if you keep these batteries at higher voltages, it will help their lifespan drastically. So what I've been doing is charging them to 4.2v and when they get down to 3.8v I recharge them. Is this how it should be done?

My main applications for these are two flashlights and an electronic cigarette. Both use a single battery configuration. From what I read a single battery config is pretty safe, is there anything I should know?

Any responses would be greatly appreciated.

 

[brted]

Re: Few questions

I've been using 14500's for a variety of things and I just want to make sure I have the right information on a few things.

I currently have some tenergy 14500 unprotected and AW14500 protected.

1. The charger is use is a tenergy TR-001. I can't seem to find any info on it. Does anybody know if this a smart charger? If I leave the unprotected batteries on it to charge while I sleep will I face any sort of danger doing this?

2. Using this same charger and the AW protected, it should be fine if I leave them on the charger overnight even if it's not a smart charger, am I right in assuming this?

I don't charge li-ion cells while I am out of the house or asleep and I take the cells off as soon as they are done. It seems like I remember some people not liking a DX charger called TR-001, but that may not be the same thing you're talking about.

3. When people talk about over discharging a battery, do they mean letting it die completely or using it in a device that drains it too fast?

I think it means letting the voltage go down too far. That number varies with some people saying 3.6V, AW says 3.5V, and some say 2.8V. I use 3.6V. It's also not good to use an excessive discharge rate.

4. I read that if you keep these batteries at higher voltages, it will help their lifespan drastically. So what I've been doing is charging them to 4.2v and when they get down to 3.8v I recharge them. Is this how it should be done?

I haven't heard that one, but I think most batteries are only good for so many full charge/discharge cycles, so if you only do a partial discharge, that can help the lifespan. I think when you won't be using the battery for a while, it should be partially discharged, not full. Also you don't want to charge over 4.2V. You could do even better by charging it to only 4.1V. It seems like with NiMH batteries and maybe others, that they would like to live between 25% and 75% all the time.

My main applications for these are two flashlights and an electronic cigarette. Both use a single battery configuration. From what I read a single battery config is pretty safe, is there anything I should know?

Sounds like you are being pretty responsible and safe.

 

[VidPro]

Re: Few questions

Brted covered it.
charged higher li-ion dont last as long indeed. if your not using it a 50% storage charge is how they store them in the wherehouses you buy them from. about 3.8v.

if you charge them to 4.1v only ever they will last many more cycles.
but 145s dont last really long anyways, so it wont much be your fault.
i think only a few factories makes the 145s the ones i have used all act similar, and die (have significant reduced capacity) before 3 years is up.
(aka you cant buy a primadonna really long life 145 like a 18650 things)

use it or lose it.

 

[mdocod]

Re: Few questions

I've been using 14500's for a variety of things and I just want to make sure I have the right information on a few things.

Hello rumm,

Welcome to CPF! I hope we can help you develop an understanding of these cells and chargers!

I currently have some tenergy 14500 unprotected and AW14500 protected.

The Tenergy brand has been very hit and miss over the years. I can't comment on the 14500 size LiCo cells, but the lack of protection combined with their historic reputation in a less than desirable charger would make me uncomfortable.

1. The charger is use is a tenergy TR-001. I can't seem to find any info on it. Does anybody know if this a smart charger? If I leave the unprotected batteries on it to charge while I sleep will I face any sort of danger doing this?

The "TR-001" designation seems to correlate to a particular charger with the brand name "trustfire." It is very likely that the same charger has been sold under numerous brand names. I like to call it the X-fire umbrella of lithium stuff. Most of the chargers I have either tested myself or seen test results of from others suggest that these chargers should not be trusted. pretty much ALL of them use less than ideal charge methods and some of them use absolutely dangerous methods that when combined with unprotected cells could lead to explosions.

2. Using this same charger and the AW protected, it should be fine if I leave them on the charger overnight even if it's not a smart charger, am I right in assuming this?

The protection on most li-ion cells kicks in at ~4.35V give or take. The reason for this is multi-fold but one that may be most important is that the makers of these cells know that many crappy li-ion cell chargers out there "cheat" and use charge voltages in excess of 4.25V during the charge. in order for the cells to charge properly on those chargers, they need to have an excessively high limit on the high voltage protection. Also, there are a few chargers out there that actually USE the high voltage protection to terminate the charge (no CV stage or reduced current towards the end of charge is used in these units). For a cell to reach a full charge with these less than desirable chargers, the protection circuit has to be designed with a higher than ideal high volt cutoff. When this type of charge method is used, and the charge rate is high all the way through till the PCB kicks off the charge, the resulting charge is often a resting voltage of 4.20V or less, which is a semi-acceptable charge method. The problem is, if your particular charger, is one of the many out there that seem to have a lack of proper termination and a tendency to trickle charger "after termination," then you could wind up drastically over-charging your cells to a dangerous level, especially the unprotected ones. Even for a "protected" cell, these lousy chargers can have seriously negative impacts on cycle life and cell safety. I would NOT go to sleep with most li-ion chargers that I have tested with a cell installed, protected or not. the dangers are likely to show up as the cells age, so don't let a sense of security develop because it is working fine right now.

The only way to confirm for yourself that your charger and yours cells are in safe working order, is to buy a volt-meter, usually in the form of a Digital Multi-Meter. (DMM). Taking measurements and confirming proper operation is the only way to know for sure if you are "safe."

3. When people talk about over discharging a battery, do they mean letting it die completely or using it in a device that drains it too fast?

Specifically, they are talking about discharging to a voltage that is lower than ideal. Your AW protected cells are designed to cut-off a discharge at about 2.5V under a reasonable load. The resulting cut-off will often result in a resting cell voltage of ~3.0V or higher, which is pretty darned dead and lower than you would want to leave the cell sitting around for a long time, but not terribly unsafe. As for your unprotected cells, if you are discharging them "all the way" until they will not run a device, then you are probably abusing the cells in a way that could lead to an explosion on future charges.

Draining too quickly is also a major concern, but is usually referred to with different terminology. For most LiCo cells, like yours, you should try to make sure that the drain rate is no exceeding ~1.5-2C. Or, 45 minutes, 30 minutes minimum run-time.

4. I read that if you keep these batteries at higher voltages, it will help their lifespan drastically. So what I've been doing is charging them to 4.2v and when they get down to 3.8v I recharge them. Is this how it should be done?

LiCo cells last longest in storage at a reduced temp and a state-of-charge of ~40-50%, or around 3.8-3.9V. Any time the cell spends at warmer temps and at full charge status or discharged status, the rate of wear and tear is increased.

My main applications for these are two flashlights and an electronic cigarette. Both use a single battery configuration. From what I read a single battery config is pretty safe, is there anything I should know?

Any responses would be greatly appreciated.

Electronic cigarette? is this device compatible with the 3.7V input?

 

[rumm]

Re: Few questions

Thanks for the replies, learning a lot. I think after reading these posts I'm leaning toward only using protected. Is there any reason to use unprotected over protected beyond cost?

The "TR-001" designation seems to correlate to a particular charger with the brand name "trustfire." It is very likely that the same charger has been sold under numerous brand names. I like to call it the X-fire umbrella of lithium stuff. Most of the chargers I have either tested myself or seen test results of from others suggest that these chargers should not be trusted. pretty much ALL of them use less than ideal charge methods and some of them use absolutely dangerous methods that when combined with unprotected cells could lead to explosions.

Can you recommend a charger compatible with 14500's that would allow more of a "dummy proof" mentality? Does one exist?

Electronic cigarette? is this device compatible with the 3.7V input?

The default batteries that come with every china kit are cheaply made 3.7v 180-280 mAh batteries. A lot of people make mods to push them to 6v using CR2 or CR123 batteries for increased vaper (or smoke) production.

 

[USACelt]

Re: Few questions

First off, :welcome:
My GF is into the E-cigs also. She just purchased a new model that came with 2 tenergy 14500 unprotected cells and a TR-001 charger. I have the Ultrafire charger, which I'm having her use instead. I was looking at picking up the Pila IBC charger with ZTS MBT-1 tester to check the batteries with. If everything I've read so far is right this is the best choice for us. I also want to get a Maha C-9000 for my Eneloops, but thats a different story. The main thought is if the Pila is the best charger for lithium ions and should she switch to protected cells ?

 

[mdocod]

Re: Few questions

Thanks for the replies, learning a lot. I think after reading these posts I'm leaning toward only using protected. Is there any reason to use unprotected over protected beyond cost?

Unprotected cells have their applications. Like when building a pack that will have a global protection installed. Pretty much all consumer devices with li-ion batteries have a global protection circuit and balance taps, so each cell lacks it's own "integrated" protection, but the cell receives the exact same effective protection.

As for loose cell consumer applications, just stick with protected cells. There are people here on CPF who have specific reasons to use unprotected cells for specific applications. For example; there are a few very high quality flashlights that have built in over-discharge protection for li-ion cells. The circuits in those flashlights is more than adequate, and having a redundant circuit on the cell only adds another possible failure point for the system. Provided the charger used can be trusted (IBC), then the use of the unprotected cell in an application like this does not really present much if any more risk than a protected cell would.

There are also li-ion cells of different safer chemistry out there (LiMn/LiFePO4) that we generally use here without protection because the intended application is high current, where protection circuits would either dis-allow the high current condition or add undesired resistance to the circuit.

Can you recommend a charger compatible with 14500's that would allow more of a "dummy proof" mentality? Does one exist?

At this time, there is only one, and it's $50. The Pila IBC.

/rant ON (you can skip this part if you want)

There is not a single other charger out there that I am aware of (I've tested many and researched many) that I would trust to give to a friend or family member to "just use it." I will personally use other chargers under supervision and only after extensive testing. I have been sent SEVERAL chargers for testing over the last few years that I REFUSE TO USE FOR ROUTINE CHARGING on my own cells because my testing revealed that they use charging methods that are dangerous. If I, as an experienced lithium-ion user am not willing to use a charger because I know how and why it's dangerous (and could theoretically circumvent the danger through intervention), then how many people out there are bringing unnecessary risk into their homes over this and are completely oblivious? There are probably hundreds of thousands of li-ion cradle chargers out in the hands of consumers right now that should be condemned.

Every time another person purchases another one of these flakey semi-unsafe li-ion chargers, we are sending the message to the builders of these chargers that the consumer doesn't care, or isn't going to put forth the effort to care about the quality of the products they buy. I fear the day when an unsuspecting consumer burns down their house, and the investigation into the cause of fire is traced back to a li-ion charger made to poor specifications. That's all it's going to take to blow this whole issue into the very public eye. Big brothers watchful eye will smell an opportunity to get involved.

Yes, I said that an eye will smell, so HA!

/rant OFF

The default batteries that come with every china kit are cheaply made 3.7v 180-280 mAh batteries. A lot of people make mods to push them to 6v using CR2 or CR123 batteries for increased vaper (or smoke) production.

I don't know much about these "E-Cigs" but this all seems kind of scary.

A product that ships with cheap unprotected lithium cobalt cells, uses a charger that probably doesn't charge in the safest possible manner. This product is not intended for use in like say, a little flashlight or clock radio, no, it's a cig simulator with a burner element in it that you hold up to your face???

This sounds bad, very very bad.

Eric

 

[mdocod]

Re: Few questions

First off, :welcome:
My GF is into the E-cigs also. She just purchased a new model that came with 2 tenergy 14500 unprotected cells and a TR-001 charger. I have the Ultrafire charger, which I'm having her use instead. I was looking at picking up the Pila IBC charger with ZTS MBT-1 tester to check the batteries with. If everything I've read so far is right this is the best choice for us. I also want to get a Maha C-9000 for my Eneloops, but thats a different story. The main thought is if the Pila is the best charger for lithium ions and should she switch to protected cells ?

I would suggest protected AW brand cells and a Pila IBC for this application.

But before doing anything else, I would actually want to do a little measurement and try to determine if there is a REASON they they are shipping unprotected cells with these products.

If these things are drawing more than an amp off of these cells, then there could be cause for concern in the long run, especially considering the likelihood of frequent use and charge/discharge cycles adding up quickly.

Eric

 

[brted]

Re: Few questions

I don't know much about these "E-Cigs" but this all seems kind of scary.

This sounds bad, very very bad.

Okay, but they are cigarettes, so they are going to kill you anyway. What's a little shrapnel in the face compared to lung cancer?

Protected vs. unprotected cells: it seems like with multiple cell applications some people say unprotected is better in case one cell trips, but I don't really see why that is.

Chargers: The Pila is the only one that uses the "correct" charging algorithm, but I don't know that that means anything else is "unsafe" or we would be hearing of a lot more fires and explosions. Not that people should be casual about charging the cells in a cheap charger, but I'm not seeing that many problems reported here. This may be partly because many of the cheap chargers aren't using a real high charging rate.

 

[csa]

Re: Few questions

Yeah... the cheap chargers aren't quite as bad as you make them out to be, but these cells don't just fly off the handle and explode very much either. I agree that the Pila is a good charger, but a bit of moderation here...

 

[mdocod]

Re: Few questions

In the last year or 3, there has been a metaphorical explosion in the loose li-ion cell market. Prior to that, a smaller handful of enthusiasts were using loose li-ion cells from very few brands.

The "cheap chargers" that trickle to 4.25V and hold cells there all day and night are in fact perfectly reasonably safe for brand new cells, even cells with mild to moderate use are going to be perfectly safe on those chargers for the first 1-3 years in almost all cases.

When that "explosion" of new cells being used in these chargers starts to reach an age bracket of 4-6+ years, I believe that the reports of explosions will start rolling in.

Eric

 

[VidPro]

Re: Few questions

Okay, but they are cigarettes, so they are going to kill you anyway. What's a little shrapnel in the face compared to lung cancer?

easier to repair

Protected vs. unprotected cells: it seems like with multiple cell applications some people say unprotected is better in case one cell trips, but I don't really see why that is.

Well they probably do say that, but when in seires THAT is when a protected battery can protect ITSELF in some of the worst situations , without protection in series, you can destroy one of the series batteries in ONE single low discharge. Might as well use Primary if your going to go off without Pack Protection or singular protection when in series.
Sure it Will cut-out , but with normal discharge rates when it cuts-out that is GOOD, because it cuts out before cell is destroyed.
bad very bad.
protection good for series, just not so fun for hotwire seires (because amp protection will cut out) , but then whats a little shrapnel in your face right
when hotwire enthusiasts use unproteced li-ion they know they are taking risk, and are often VERY carefull and aware of battery voltages, and stop well before discharging any single cell to far. (in theory
Myself I find it is very hard to do, and its not so fun having to keep up with exact discharge timings and stopping early and all, and i screw up everything already ;-), so if i did that i would probably ruin cells fast :-(

 

[mdocod]

Re: Few questions

To reinforce and elaborate on what VidPro is saying;

Protection circuits are MOST IMPORTANT when cells are being used in series. It is not uncommon for cells to discharge down somewhat unevenly from one cell to another in a series discharge. While the current output is equal across the entire series pack, some cells may discharge more quickly than others if they are holding a higher voltage due to temperature differentials (not uncommon in devices that produce heat on one end, like a flashlight, or maybe like an electronic cig). Perhaps more important, is the fact that no 2 cells are exactly the same in performance and capacity. Every cell that comes off the assembly line will have a slightly different true capacity and resistance than any other cell. In a given production run, there will be a range that could be represented by a bell curve for capacity. With cheaper cells, the bell curve is wider and shallower. The possibility of having cells up to 10% or more difference in true capacity is not out of the question.

When a higher capacity cell is mixed with a lower capacity cell in series, in many devices, the lower capacity cell can be severely over-discharged or even REVERSE charged before the better cell gives up. On the first dozen cycles or so (possibly up to several dozens), doing this to unprotected cells may not seem to generate any noticeable negative results, but over time, the lower capacity cell is abused more and more, which results in lower and lower capacity, which subjects the cell to an ever increasing amount of wear and tear. It's a vicious cycle. That cycle is the recipe for taking what would be a safe cell, and slowly converting it into a very dangerous cell ready to blow at any time.

Using protected cells, even if the cells themselves are of lower quality, can eliminate a large portion of this risk because the device will be shut down by the protection before an under-performing cell can be heavily abused. Using higher quality cells in conjunction with protection circuits reduces the risk factor by an even greater margin.

Eric

 

[USACelt]

Well, I talked to her about switching to protected batteries, but I don't think they will fit. The battery holder appears to have a vent hole in the bottom, so hopefully that will help in case of a catastrophic failure. I may see about getting the tube bored bigger. I don't forsee any problems with the device, I'm just worried about the chargers.

(A side note, these electric cigerettes are not smoked. The have an element that heats a liquid which turns into a water based vapor. You can control the amount of nicotine, from 100% - 0% It's a great way to stop smoking for some. It's helped my Gf a lot.)