Hi discharge vs low discharge 18650

[Rhinny2012]

Somewhat new to this whole thing, so could someone clarify this for me? I assume a battery that says 30 amp discharge is higher than a 10 amp discharge. But why would I want one over the other for a light such as a Zebralight sc62w or a Nitecore MH20?

 

[hazard2036]

Hey mate the higher discharge rates come in handy if you are running a direct drive set up. If your light is stock not much point on running a high discharge cell it will only give you a slight bump in power. The two light you mention you are better of buying standard cells with a higher MAH rating. They will be a cheaper buy and give you longer run times then the high discharge equivalents .

 

[Rhinny2012]

Excellent. Thank you for the clear answer.

 

[hazard2036]

One more advantage to high discharge cells is there overall length may be a tad shorter. That may come in handy in some lights.

 

[StorminMatt]

One more advantage to high discharge cells is there overall length may be a tad shorter. That may come in handy in some lights.

The only reason why a low discharge cell may be longer is if the cell is protected (high discharge cells are almost always unprotected). But other than this, there is no reason why a higher discharge cell would be shorter. If you want a lower discharge, higher capacity cell that is shorter, you can always opt for unprotected cells.

Speaking of the issue of high vs low discharge, it should also be noted that many of the latest high capacity cells actually allow a higher discharge rate than those of a few years ago. A good example of this is the highly popular 3500mAH Sanyo NCR18650GA, which can be discharged at a rate of up to 10A continuous / 15A pulse (vs maybe 4-7A continuous for earlier cells like the NCR18650B). Although these newer cells cannot match true high draw cells (which may allow up to a 25-30A discharge), they can still work well in many lights that would have required high draw cells (and the resulting sacrifice in capacity) not too long ago. Needless to say, these higher discharge, high capacity cells have made true high draw cells obsolete for a good many applications.

 

[Gauss163]

Somewhat new to this whole thing, so could someone clarify this for me? I assume a battery that says 30 amp discharge is higher than a 10 amp discharge. But why would I want one over the other for a light such as a Zebralight sc62w or a Nitecore MH20?

Unfortunately you cannot always assume that because there are some unscrupulous rewrappers who inflate current ratings by using pulse ratings instead of continuous ratings. Further, there are no industry standards for reporting pulse ratings, so they can spin the numbers however they like. Efest is notorious for grossly exaggerating current ratings, e.g. see Mooch's extensive tests. Caveat emptor.

 

[paojerokid]

Didnt mean to hijack the thread...
Will this perform good with the nitecore mh20?
Will it make a huge difference at turbo mode if I use a high discharge rate 18650? What 18650 would you recommend? Thanks.

 

[18650]

Didnt mean to hijack the thread...
Will this perform good with the nitecore mh20?
Will it make a huge difference at turbo mode if I use a high discharge rate 18650? What 18650 would you recommend? Thanks.

The MH20 looks like a standard 1000 lumen single 18650 cell light which would easily be sustained by any 10A capable cell like the Sanyo NCR18650GA. The one in your picture looks like one of those cruddy Trustfire batteries which many of us would not trust for a second. For the OP, high discharge cells will have less voltage sag under high current loads compared to standard "low discharge" cells. Aside from direct drive lights mentioned above, this is also useful for boost driver based lights that have high current requirements for the highest modes. (longer runtime on highest modes before dropping out of regulation)

 

[ven]

It looks like a *****fire cell so the answer is no, it won't perform well. Likely the mah will be a lot lower than shown on the label. Probably won't hold turbo for long if at all. Sanyo/pany GA cell as suggested offer a good balance of performance/run time.

 

[staticx57]

I would recycle that cell you have there. It no doubt spent a questionable life before it was rewrapped by some company in china and sold.

 

[Taxman]

Can someone please provide a laymen's explanation of what it means when you say "direct drive"?

Maybe give an example of a light that is diect drive and one that isn't? Are the custom tri and quad LED lights direct drive versus my ZL SC600 MKIII HI being stock and regulated?

Thanks

 

[HKJ]

Can someone please provide a laymen's explanation of what it means when you say "direct drive"?

Direct drive means led theoretically connected directly to battery. There will always be some resistance in the connections, spring, switch and some may even add a small resistor.
Some do also use a fet driver that switches only on/off, it has very low resistance, but by switching on/off fast enough it is possible to regulate the brightness (This is called pwm and is also used on regulated drivers).

Not all will call all the above direct drive.

 

[Taxman]

Direct drive means led theoretically connected directly to battery. There will always be some resistance in the connections, spring, switch and some may even add a small resistor.
Some do also use a fet driver that switches only on/off, it has very low resistance, but by switching on/off fast enough it is possible to regulate the brightness (This is called pwm and is also used on regulated drivers).

Not all will call all the above direct drive.

Thanks HKJ - I have learned almost all I know about batteries from your site. I am familiar with PWM. And I believe I understand now.

 

[niktak11]

Didnt mean to hijack the thread...
Will this perform good with the nitecore mh20?
Will it make a huge difference at turbo mode if I use a high discharge rate 18650? What 18650 would you recommend? Thanks.

I have two of these that I got for free. Dispose of them. The actual capacity is under 1000mah

 

[Lexel]

In a 1000 lumen flashlight a low drain cells with PCB will perform very well as they drain about 3A in highest mode.
Panasonic 18650B cells with PCB are pretty cheap

High drain cells may be good on direct drive flashlights, but you probably need a spring bypass as well to see a difference
the nitecore flashlights run in constant current mode, so high drain cells doesnt increese output

Ultrafire cells have a recycling logo on em guess why!

I did spring bypass on my flashlights and run them with 18650B cells with PCB

 

[rojigga]

Didnt mean to hijack the thread...
Will this perform good with the nitecore mh20?
Will it make a huge difference at turbo mode if I use a high discharge rate 18650? What 18650 would you recommend? Thanks.

That's an EBL battery. Shown here: https://www.amazon.com/dp/B016ZPBHAK/?tag=cpf0b6-20. The low discharge rate refers to shelf life discharge, as they use that as a selling feature.

 

[StorminMatt]

Another thing to keep in mind is that, these days, high draw cells are gaining capacity faster than low draw cells. The capacity of high draw cells is rapidly closing in on that of lower draw cells, and is in some cases almost equal. For instance, the REAL capacity of a Sony VTC6 is only about 100mAH lower than that of an NCR18650B. With this in mind, along with the fact that the VTC6 holds voltage better, the VTC6 is the better way to go if price is no object.