Protected or unprotected - for my use?

Batteries and Chargers Rechargeable Batteries
1

New on this forum, so try to learn as much as possible.

I know the basic around protected and non protected batteries, so that fine. But I do not know where to use what type.

My main usage is flashlights (mostly Ultrafire WF-501B or similar products)(aka cheap stuff)
And then most recent, power banks.
Thats it, for now.

I have some few protected batteries from a couple of years back, and just ordered 8 x icr18650 – 26fm protected batteries.

In my power banks, I can’t use protected cells, since they are to long. There I need flat top batteries, the best is max hight of 64.8x+.

So then there is my flashlights. Is it best to use protected cells there, or non protected cells? The last 8 years or so, I mostly have used unprotected cells, and I have not had any issues.

But now that I have new protected cells (when they get here), do you recommend that I change the batteries in my flashlights to protected cells?

And what other products benefits from protected cells?

Last question, I have a package of sanyo ur18650zy flat top batteries on the way, are they protected or not?

2

The main advantage I see for you is protection against over-discharge and short circuits.

I pretty much only use unprotected cells, but if I’m giving a light to someone with questionable diligence and attention to detail, I tell them to buy protected batteries.

3

Have chargers something to say in this?
I have use a couple of Soshine H2 chargers to charge my batteries. I now have ordered a Nitecore D4, along with BT-C3100, and Liitokala lii-500 (stupid first order one, see the reviews, to find something better, then order, etc)

4

Protected cells are great for novice users while they’re learning to ins and outs of li-ion cells.

I use unprotected cells on light lights, just make sure not to discharge them too far and you should be fine. A slight issue arises when you use cells in series because if one discharges faster than others, it can cause reverse charging, which kills the battery.

5

In flashlights and other appliances with several li-ion cells in series protected cells are in order. Or at least circuits that monitor the "balance", temperature or voltages of the battery pack. Experienced users with suitable equipment can get away by monitoring the capacity of the cells when they are charged in an analysing charger. Otherwise it is even possible that a cell with very different capacity from the other cells get reverse charged and destroyed or even brought to explode and catch fire.

In appliances with several li-ion cells in parallel unprotected cells can be used, because the group of cells provide protection against problems in an individual cell being discharged too fast or too much. Or even charged too much.

Parallel cells are not all safe. Before you put them into the device you should make sure they are att the same voltage, otherwise there may be a very high current as the voltages of the cells are equalized. That may cause wires to burn up or even solder to melt. You can make sure all cells are att the same voltage by charging them, then they will all be between 4.2-4.1 volts. That is fine.

In cheap flashlight, without low voltage protection, for single li-ion cells, it may be prudent to use protected cells to avoid discharging the cell too much and permanently destroy or reduce available capacity. It is even possible that a cell destroyed by over discharge will overheat when you try to charge it, with possibly dangerous consequences.

In single cell flashlight with low voltage protection you can use unprotected cells without problem. It might even be necessary in order to get enough current to the LED. A protection circuit may limit the current.

So for newbies with cheap flashlights without low voltage protection, and possibly with cheap and unreliable chargers: Use protected cells.

For experienced users who know the danger of li-ion cells in series and who are able to minitor the capacity (not just the voltage) of the cells as they are charged, unprotected are fine.

In power banks (they always(?) have low voltage protection) unprotected cells in individual circuits or parallel usually is fine.

When you hear about exploding flashlights I assume that the user has put in one new/fully charged cell and one (perhaps partially) discharged cell in series. And then turned the high-powerd flashlight on. And possibly even managed to put it in the mouth in time for the discharged cell exploding. :X

6

Generally accepted advice is to use protected cells if you are using more than one in series. Reverse charging can gradually damage a NiMH cell (causing outgassing and loss of capacity) but is apparently much more catastrophic with Li-Ion (think pipe bomb).

If using unprotected cells in a series setup (this does not normally include power banks which are usually parallel) then you need to use matched sets and spot-check the voltage periodically. Better just to use protected cells in that case.

Protection circuits can guard against shorts, overcharge and overdischarge, all of which can be dangerous. They do however limit the maximum current that the cell can supply so are not favoured in high performance "modded" hot rod lights.

If you do use unprotected cells in your flashlight, it would be helpful if the driver had a low-voltage cut-out. Either that or replace/recharge as soon as the light becomes dim. And recharge the cell as soon as possible rather than leaving it sitting at low voltage for extended periods of time.

Power banks will normally have a low-voltage cutoff built into the circuitry. Many users find these are a good way of utilising second-hand laptop pulls or other cells too old to drive a powerful flashlight. Try to make sure they are at very similar voltages when you first put them into the bank and after that they will take care of themselves.

7

So I understand that so long as I don’t put batteries in series, unprotected will be OK. So my one battery flashlights, is safe to use with unprotected cells. But it don’t hurt to use protected cells, when I have them?

I have now checked all my old batteries, some almost 8 years. And it’s seems like I almost have got protected cells, of 40 batteries, just 4 was unprotected.
And that explains why no of my batteries really fit in my new power banks that I got, since the high was between 67mm and 69mm on all the batteries I have.
The battery with a high of 67mm, fits if I press it in to the power bank, but then no battery I have now is flat top.
So sure with flat top batteries, they will fit perfect in my power banks.

8

Yep, just don't ever run the unprotecteds in series and things should be fine.

9

Maybe start a new thread, but try to use this one.

I read allot of high drain batteries of 10 - 30A. Will a high drain battery give me any extra power for flash lights (type Ultrafire WF-501B) and/or power banks?
Or are they more for e-sigs etc?

10

High-drain batteries are really not going to matter for any of your lights--unless they are modded and/or direct-drive and can use the extra boost. A current-controlled light with power regulation (like most of the high-end brands) will also not benefit from high-drain. Ecigs I don't know about.

I have a couple of these high-output type batteries, but I don't worry about having more of them because any light that can utilize these batteries will not run at full capacity for very long (since they aren't regulated, and I'd rather have regulated, consistent output).

11

I am a relative newbie who cannot really add much to what the experts here have already said.

I have read, however, that the quality of the various XXXX-Fire brand flashlights is hit and miss. Even within the Ultrafire brand, there are different manufacturers (and knock-off makers) producing products of varying quality. Sometimes the ones that say they have a low-voltage cutoff do not. For this reason, using a protected battery in one of them might be a good idea.

I don't know a thing about the Ultrafire WF-501B you have, but the fact that you have used it for years is a good sign.

You can test yourself to see whether it has a functioning cutoff. Just put in an unprotected battery, and turn on the light. Stop periodically to carefully monitor the battery with a volt meter. If the voltage falls below about 2.8v, you should stop the test. It is likely that the flashlight does not have a cutoff. On the other hand, if the flashlight cuts off before then, you probably have a working cutoff. Many of the good ones will cut off around 3.0v or higher.

If the voltage of a battery falls below 2.5v during your test, you may have a problem. Your battery may (or may not) be damaged, and it could be dangerous. Be careful. HKJ reports that a large number of batteries are rated to go down to 2.5v. There are some models, however, for which that can damage a battery. With those models, you might damage a battery at the higher voltage (typically around 2.8v or above) stated by the manufacturer.

IIRC, HKJ stops his tests at 2.8v, and so should you.

With Li-ion, battery life can be extended by avoiding extremes of charge and discharge. In general, therefore, you want to recharge a battery when its voltage falls to around 3.0-3.1v. This is true even for batteries that are rated to go lower. For this reason, I see little advantage in using unprotected batteries. In a flashlight, the only time unprotected batteries are absolutely necessary is in high-power/high-current models or in devices where protected batteries are too large to fit.

Think about what has to go wrong these days before a modern airliner crashes. When equipment, rather than pilot error, is the cause of a crash, most reports indicate that two or three systems and/or backups failed at the same time. It usually takes more than one failure to bring down an airplane.

That's how I view my decision to use protected batteries (when I can). Sure, most of the lights I use already have a low-voltage cutoff. If my flashlight circuits fail, however, and a flashlight does not cut off properly, I have a backup.

Of course, with unprotected batteries, you also have a backup. It's the person running the light. Actually, he or she is the primary protection system. If one notices a light losing its brightness, then it's probably time to recharge. The cutoff protection built into a flashlight is usually just a backup. With protected batteries, you have a second backup.

I tend to discount anecdotal reports of users who have switched to unprotected batteries and have not experienced a problem. What happens to one careful person using a hundred or two hundred cells is not indicative of general circumstances. When they are used carefully, Li-ion batteries simply do not fail that often. The reason I use protected batteries is to reduce the odds that I become the one person in ten thousand or a hundred thousand who gets into trouble.

Just my two cents. YMMV.

12

Thank you for your reply.

I got some (now I know) fake Ultrafire flashlights some weeks ago, and one thing I did was to take a protected 18650 Ultrafire 5200 battery (gray color) and put in on, and just let it stay lid. It was light there for over 36 hours, before I turned it off (the light was then really poor, but still, you could have used it for reading a book or something). But the test had damaged the cell, and my charger told med right away that it was a poor cell (and it was not before the test, used the same charger to fully charge the battery.

Good thing that I did not do this with a unprotected cell then…

13

In this case, the protection in your battery never triggered.

It is likely that neither the flashlight nor the battery had low-voltage protection circuits.

XXXX-fire batteries are even spottier than the flashlights that carry that brand. When they are given ridiculous capacity ratings such as the one you mention, they are certainly fakes. Many turn out to be unprotected 18650s that have been pulled from used laptop battery packs.

14

I now only use protected cells in lights without low voltage shut off or lights with multiple cells in series.In multiple cell lights I also keep the set of cells married to the light until replacement.

15

If in doubt at all, use protected. There is no downside unless you have modded hotrod, high amp lights.
You must be sure your flashlights have low voltage warning / protection. If not use protected batteries only. If a battery is allowed to discharge too low it becomes internally damaged and will be at increased risk of venting with flame or exploding in a light. This can happen at any time in the future once a battery is damaged.

Xxx-fire batteries are junk, usually dangerous junk. I’d dispose of them. Often they say “protected” on the wrapper but it’s a lie. Sometimes they are rewrapped used, worn batteries that were discarded.

The batteries with high fake capacities like 5200 are the ones most likely to be rewrapped worn, discarded cells with wrappers that lie about having protection.
How to see if your battery is protected

16

Yes I know about the fake Ultrafire batteries. Will check the actual mAh when I get one of my three new charger that can also test the batteries. If they have 4500 or lower, I will trow them away.
I really hope the Sanyo batteries I got from Alibaba is real, and I did buy from a honest seller. If not, I have ordered some Samsung 26FM (bot protected and not protected) and some Samsung 30B batteries. All in all I will have more batteries that I need.

17

They will be 3200 or lower, likely much lower.

18

You where correct, they was on max 1000mAh. So just crap.

19

High drain vs high capacity depends on how much current you need. High drain in general just means low internal resistance but comes at at the cost of storage capacity so choosing the right cell for the job will maximize output and run time. There are no 18650 cells with more than 3500 mAhr capacity and even 26650’s top out not much over 5000 mAhr. For high drain an unprotected IMR cell is best since it can maintain voltage at high current due to low internal resistance but only has maybe 2500 mAhr capacity. For lower drain usage cells with higher internal resistance and higher capacity will last longer.