Test / Review: Hi-max 18650

Does it affect thickness greatly?

Looks good to me. Durable insulation is an excellent feature imo.

Yes it does.

The old Hi-Max will go in the Catapult V3 tubes but the new ones only one of them will fit. I'll have to check them on other lights.

The same goes for the Sunwayman T40CS.

They do go in the Crelant 7G5. One is a little bit snug but still goes in. It does get stuck a little on the way back out and you got to shake the light to get it to come back out.

Leave it out overnight at sub zero temps (assuming you have a decent winter outside) and see if the battery comes out. ;)

It seems the good idea turns out as an occasional annoyance...

Or toss it in your freezer.

they dont fit a Zebralight H600 either. I have stripped a couple of them so far. its a bummer since the outer wrapper looks tougher then the inner one, but without it they are no worse off then normal batteries

edit: they dont fit a zebralight SC60 either...looks like all the wrappers will be coming off for me.

Wish we could get a group buy on these, they are great batteries. But I don't see paying $8 or 9 apiece for 18650's.

http://www.ebay.com/itm/12pcs-18650-2600mAh-Protected-Li-ion-Battery-3-7V-/220944817348?pt=US_Batteries&hash=item3371565cc4

USD $5.25 shipped per cell. TF2400's can be found cheaper but I didnt want to gamble on the quality. So far they seem nice but I havnt cycled them much or drained them.

I am thinking the same way, I need some 18650 cells for laptop battery, trustfire 18650 is really cheap at 3,5$ a piece, but the quality from DD changes a lot...

What's the recommended charge rate for an 18560 such as these. Also, what would be the maximum safe charge rate?

It can vary somewhat depending on the exact chemistry and characteristics of the cell, but 0.7C is a fairly common max charge rate for LiCo cells.

Assuming a decent capacity 18650 cell (obviously very different if we were talking about 16340s, 14500s, etc. which have smaller capacities and need lower charge rates) I tend to stick to 1A for charging.

Obviously that means long charge times for higher capacity cells, but I'd rather treat Li-Ion cells gently rather than push them to the limit.

Thanks for responding :) Unfortunately it takes approximately 200 minutes to complete at 1 amp. I was hoping I could safely charge them at a higher rate without shortening the life of my cells..

thats 0.7 x Capacity .. so around 2500mAh x 0.7 = 1750mAh , this is the ideal recommended charge rate by some ..

Max charge rate is quoted as 1c in this case it would be 2500mAh ....

Faster charging will result in slightly less capacity , more stress on the battery , shorter over all life , and possibly faster degradation .

But if you buy new batteries every 12 months = Who cares ..

Say you stocked 6 18650 and used them for your lights , every 12 months or so you should test them , to see if they have degraded , some cells may have [ depends on individual cell ] you may wish to replace such , or what ever ..

Me I just test them when I get a feeling there not performing well [ test for capacity ] , and if they have lost significant capacity they get the pink slip .

Conventionally 0.7C so 2600*.7=1800mA

I'd not go above 2500mA as it won't actually fill up any faster and is likely to be less completely charged - most chargers just stop at a tenth of the original charge rate. So at a lower rate you are more likely to get a more complete charge. The CC/CV method recommended for lithium ion cells ought to work as charge it at a constant current till it hits 4.2V then let the current drop till it is a tenth of the original charge rate. Then stop.

Also, at higher charge rates, it is likely that the cell will get hotter than is desirable. At silly high charge rates it is likely to end its life fairly spectacularly. If you get lithium metal plating out on the cathodes then Bad Stuff is going to happen.

Remember that you want to keep the lithium in solution - it's when you get lithium metal appearing that stuff can get interesting. It takes time for the ions to float around inside the cell to do what you want them to. If you don't give it enough time then lithium metal dendrites will form and can cause internal shorts which are not things you want to have happen.

So high charge rates are strongly contraindicated for lithium ion cells.

I've had my set of HI-MAX cells for approaching a year now.

Considering they all haven't been kept at storage voltage, I suppose they aren't doing too badly. But they haven't had a very hard life cycle count wise, less than 20 cycles each I would say.

Here's the capacity measured.

1A Discharge

Cell 1: 2328 mAh
Cell 2: 2226 mAh
Cell 3: 2248 mAh
Cell 4: 2231 mAh

I will repeat the test @ 500mA discharge current on a couple of them.

whats maximum discharge rate of these cells?

2C is generally considered Maximum , but depends on the manufacturers ratting …

Some 18650 cant maintain 1.5C , so ?

Its a variable , and if you plan on high current , best to buy a proven battery .

Thanx

^Wrong thread?