Looking for a no-headaches 18650 cell recommendation

flatline

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It's been 5+ years since I gave any thought to Li-ion cells, but I just ordered a Malkoff MD2 and I don't want to invest in a bunch of CR123 primaries.

Here's my current setup:
one 8-year-old Pila charger (highly recommended in 2010, probably nothing special now)
two 8-year-old protected AW RCR123's that I've been cycling through my HDS clicky for the last 8 years
six unprotected Sanyo 18650 cells that I salvaged from a laptop battery 9 years ago (probably 14+ years old at this point).

I lost my S-mini 4+ years ago and haven't used the 18650 cells since. They're super old and I don't want to worry about using them, so they're going in the recycle bin.

In theory I could use my two RCR123s to power the MD2, but there's no telling how many cycles I've put on these 2 cells over the last 8 years or what their actual capacity is now and so I'm totally unwilling to put them in series together.

My only safe option with what I've currently got is to use a single RCR123 with a spacer to power the MD2.

I figure I need to get two new 18650 cells, one for the light, one as a spare. I don't need large capacity. I don't need to sustain high current draw. The spare will be kept fully charged, so if a particular chemistry degrades less when charged or can sustain more charge cycles than another, that's a plus even if it's at the cost of capacity.
The cells will never be used in series, so there's no worry about matching cells. I've read that the M61 will drop into direct drive when the cell voltage gets below 3.4v, so I should never accidentally run the cell completely empty.

Basically, I want a cell that is least likely to give me any sort of headaches. I'll gladly trade capacity for peace of mind.

Thanks!

--flatline
 
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flatline

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That's an interesting suggestion. One LFP cell with a spacer wouldn't provide enough voltage to keep the M61 in regulation but two LFP cells in series would give me about 45 minutes of regulated output without any of the dangers of the more common li-ion cells.

I will definitely give that some consideration. It looks like a charger and 4 cells can be had for about $20 + shipping.

So is this where most flashaholics are heading now days or are regular protected 18650's still king because of capacity?

--flatline
 

zespectre

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DISCLAIMER: NOT a subject matter expert on 18650 batteries!

So right now I'm using a set of EBL 18650 Battery Lithium-ion 3000mAh
(4 pack for $12 at the "A" place) and they come with a set of carry boxes.
They are "button top" protected cells, but they are shorter ones so for some lights I use tiny neodymium magnets to extend them.

I've been running them in a several light now including a Klarus G30 and Klarus G35 without trouble.

I have a Nitecore D4 charger. I like it a lot for it's flexibility but it is nowhere near the fastest charger you'll ever see. That is okay with me, slower is easier on the cells :)
 

ChrisGarrett

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Quality 18650s by the Big 5: Sanyo-Panasonic, Samsung, LG and Sony are inexpensive, even the protected cells sold by rebranders like Orbtronic, Keeppower, Efest and a host of others.

With a little bit of attention, they're safer than riding a public bus.

Don't overthink things.

Chris
 

JoeRodge

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Does it require a protected cell? I've had great success with Keeppower and Eastshine. They both use Panasonic/Sanyo NCR18650GA cells. If it requires an unprotected cell get the flat top NCR18650GA itself. Illumn sells them. Good luck.

Top, high quality cells, highest capacity and very reliable.
 
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Timothybil

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I have been using Nitecore and 30Q sells with no problem. I started with a Nitecore 14 v2 charger, and now use an Xtar VC4, which is a very nice charger.

I can see getting four good cells for $20, but with a charger thrown in, I would have my doubts. I got and Xtar VP2 for the lower charge rates for my 10440 and 14500 cells, but it will also charge LiFePO4 cells just fine. Just no NiMH.
 

flatline

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I can see getting four good cells for $20, but with a charger thrown in, I would have my doubts. I got and Xtar VP2 for the lower charge rates for my 10440 and 14500 cells, but it will also charge LiFePO4 cells just fine. Just no NiMH.

batteryspace.com is where I found the charger + 4 LFP CR123A sized cells for $18.90 + shipping. The charger by itself is listed at $11.50 and the cells are between $1 and $2 each depending on the quantity you buy. Whether or not this is too good to be quality, I have no idea. It's just the first site I found.

--flatline
 

flatline

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Does it require a protected cell? I've had great success with Keeppower and Eastshine. They both use Panasonic/Sanyo NCR18650GA cells. If it requires an unprotected cell get the flat top NCR18650GA itself. Illumn sells them. Good luck.

Top, high quality cells, highest capacity and very reliable.

It's my understanding that protected cells work just fine in the MD2.

The Malkoff site sells the Keeppower protected cells for use with their lights (but are currently out of stock), so it's tempting to just pick up 2 Keeppower cells based on the Malkoff recommendation and be done with it. But I figured this might be a good time to re-educate myself on the options available. A lot can change in 7 years.

--flatline
 

WalkIntoTheLight

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You say you don't need high capacity, but will keep a spare cell fully charged at all times.

Why don't you use a high-capacity cell, but only charge it to 4.0v ? It will be 80% charged at that level, which still gives you lots of capacity, but it will be much easier on the cell kept charged. It will degrade far more slowly over time at 4.0v, compared to 4.2v.

This way, you get the advantage of a high-capacity cell if needed (charge it to 4.2v before use), and the longevity of a cell kept at 4.0v if you choose to go easy on it.

Use the Panasonic GA cell. High capacity.
 

flatline

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You say you don't need high capacity, but will keep a spare cell fully charged at all times.

Why don't you use a high-capacity cell, but only charge it to 4.0v ? It will be 80% charged at that level, which still gives you lots of capacity, but it will be much easier on the cell kept charged. It will degrade far more slowly over time at 4.0v, compared to 4.2v.

This way, you get the advantage of a high-capacity cell if needed (charge it to 4.2v before use), and the longevity of a cell kept at 4.0v if you choose to go easy on it.

Use the Panasonic GA cell. High capacity.

If I had a charger that I could set the termination voltage on, I would totally do that. However, my Pila charger simply has a red light and a green light. When the green light turns on, it's a 4.2v. I'm not willing to hover over the charger with a multi-meter.

Are there easy to use chargers available that have variable termination voltage settings?

--flatline
 

ChrisGarrett

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batteryspace.com is where I found the charger + 4 LFP CR123A sized cells for $18.90 + shipping. The charger by itself is listed at $11.50 and the cells are between $1 and $2 each depending on the quantity you buy. Whether or not this is too good to be quality, I have no idea. It's just the first site I found.

--flatline

Two RCR123A 3.2v cells are going to be of questionable quality, as they're just harder to source and we have fewer sources.

Cells run in series, are best run with protection circuits and even then, you should monitor them for uniformity across usage, to make sure one isn't weaker than the other and initiate 'reverse charging'.

Finally, since you're running two RCR123As in series, you compound voltage, but not capacity, so you're really stuck with about 500mAh-600mAh, albeit at ~6v.

Save yourself the worry and just get the Keeppower protected cells that use say...the Sanyo-Panasonic NRC-GA, or the Samsung 30Q, or the Sony VTC-5/5A/6, or the LG MJ1, for example.

With a little bit of searching, you can find the rebranders using the above and you'll be good to go. The 3.7v (18650) output shouldn't be an issue.

Chris
 

StandardBattery

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If you don't need high capacity the light might be better run with 2x18350 for regulated output. Your backup and be one of the latest protected 18650 with a GA or other decent cell. Check that this configuration is compatible, and get only the latest 18350 with ~1100mAh from a trusted source.
 

WalkIntoTheLight

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If I had a charger that I could set the termination voltage on, I would totally do that. However, my Pila charger simply has a red light and a green light. When the green light turns on, it's a 4.2v. I'm not willing to hover over the charger with a multi-meter.

Are there easy to use chargers available that have variable termination voltage settings?

--flatline

I use the Nitecore SC4 charger, which gives a readout of the voltage. It won't terminate automatically at less than 4.2v, but you can pull it off when you notice the readout gets to around 4.0v - 4.1v. Normally, I charge my cells fully, but if I know I'm not going to use a cell for awhile, I'll pull it off early.

Even with a simple charger like yours, you probably have a good idea how long it takes to charge your cells if you measure the voltage before you start charging. Since charging goes to a CV phase around 4.0v-4.05v, you get plenty of time during the last part of charging to guess when to take it off.
 

Modernflame

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Since you're not using them in series and you seem to have a grasp of battery safety, I don't see any need to worry. I picked up a pair of Keeppower 3400 mAh 18650's from the Malkoff website in August of 2016. They've been true workhorses. In your position, I'd just keep it simple. Still probably a good idea to stock a few primaries for emergencies, but the Keeppower cells will easily bear the burden of your M61.
 

flatline

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Thank you all for your responses!

I'm going to go ahead and order a pair of KeepPower 3500mAh protected cells. They seem to be the modern iteration of the technology I'm already familiar with and already have a quality charger for, so it seems like the easiest way to move forward. And they seem to have an excellent reputation the way that AW did the last time I went shopping for cells.

I love this place :)

--flatline
 

JoeRodge

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Thank you all for your responses!

I'm going to go ahead and order a pair of KeepPower 3500mAh protected cells. They seem to be the modern iteration of the technology I'm already familiar with and already have a quality charger for, so it seems like the easiest way to move forward. And they seem to have an excellent reputation the way that AW did the last time I went shopping for cells.

I love this place :)

--flatline

Yeah, you really can't go wrong with that choice. Glad you were able to make a decision :).
 

flatline

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I got my Keeppower 3500mAh batteries before I got the MD2 that they were destined for so I pulled out my old MG L-mini and discovered that the batteries wouldn't fit.

Are 18650's wider and longer than they were 8 years ago?
If I want to start using an 8 year old 18650 light, do I need to get a modern 17650 battery to use in it?

--flatline
 
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