Test/Review of EnerPower+ 18650 3400mAh (Blue)

[HKJ]

[size=+3]EnerPower+ 18650 3400mAh (Blue)[/size]

Official specifications:

• Nominal Voltage: 3.6V
• Capacity: 3400mAh
• Minimum Capacity: 3350mAh
• Standard charging current: 680mA for 5.5 hours to 4.2 V / 0.2 C
• Maximum charge current 0.5 C/1700mA
• Protection: 7A
• Deep discharge protection: at 3V
• Nickel base plate for added durability
• Diameter: 18.5 mm + / - 0.01
• Length: 68.8 mm + / - 0.01
• Weight: 48g

This is the latest cells from Panasonic with the highest capacity.
The cell used can be discharged down to 2.5 volt, in my test I only discharges to 2.8 volt, i.e. I do not measure the full capacity. But then, not all lights will be able to use the full capacity.

These batteries are good at both low and higher current.

[size=+3]Conclusion[/size]

This battery has higher capacity and better high current capacity than its predecessor (3100mAh/NCR18650A).
EnerPower has added a good protection to a good cell, making a very good battery.



[size=+3]Notes and links[/size]

The batteries was supplied by ENERDan for review.

How is the test done and how to read the charts
How is a protected LiIon battery constructed
More about button top and flat top batteries

 

[pabcor]

Impressive! and you can buy on ebay too.

 

[candle lamp]

Great review. Many thanks for your time & effort as always. HKJ! :thumbsup:

I don'k know how I check out the protection test graph. Could you explain it please?

 

[HKJ]

I don'k know how I check out the protection test graph. Could you explain it please?

That chart shows a couple of result.
The point where the line stops is the maximum current I can draw, i.e. it is where the protection kicks in. With unprotected batteries I usual stop at 15A
You can also see the voltage from the battery at high current loads, but remember that it is for a fully charged battery and only for a short time.
The slope of the curve is the internal DC resistance of the battery.

The PCB protection is temperature sensitive, this means that a continuous load will trip at a lower current than I measure

 

[roadkill1109]

Is it better to get the Panasonic 3400 like this (protected) rather than just getting the ones that are unprotected? Since these are high-drain, high-capacity cells, wont the protection kick in all the time so you wont maximize the cell's potential?

Based on the chart, it cuts off at 9A, but as HKJ stated it can go as high 15A unprotected. (Did you just stop because the battery might burst? hehe)

 

[HKJ]

Is it better to get the Panasonic 3400 like this (protected) rather than just getting the ones that are unprotected? Since these are high-drain, high-capacity cells, wont the protection kick in all the time so you wont maximize the cell's potential?

Based on the chart, it cuts off at 9A, but as HKJ stated it can go as high 15A unprotected. (Did you just stop because the battery might burst? hehe)

The 15A is just my standard limit and is much higher than the batteries is rated for, my excuse is that I only apply the current for a short time. If you match the battery to the application you will not have problems with the current limit in the PCB protection.

If you are using the battery at high current drain, you will wear it out at a much faster rating and for some batteries it might also increase the risk of fire.

The protection protects against more than one problem:

1. Over discharge. If you discharge the battery to much it will take serious damage. For me this is a very important function, I hate throwing batteries out, just because used the light to long time.
2. Reverse polarity in multi battery lights. This is something you do not want to happen!
3. Short circuit, the PTC in the battery does also protect against this, but is much slower.
4. To high current, that will wear the battery down (Not all protections are good here, some have to high a limit). I have not seen the datasheet for the 3400mAh cell yet, but my guess is that the protection in this battery is very well matches to the batteries current capability.
5. Over charge, if you have a defect charger, this protection will save the day.

 

[candle lamp]

That chart shows a couple of result.
The point where the line stops is the maximum current I can draw, i.e. it is where the protection kicks in. With unprotected batteries I usual stop at 15A
You can also see the voltage from the battery at high current loads, but remember that it is for a fully charged battery and only for a short time.
The slope of the curve is the internal DC resistance of the battery.

The PCB protection is temperature sensitive, this means that a continuous load will trip at a lower current than I measure

Thanks a lot. HKJ!

As an aside, I remember the protection circuit kicks in at around 2.8V for my 18650(2600~3000mAh) protected cells(ICR) which have SamSung or LG bare cells, due to their low voltage discharge safety (something like guide line). The lowest voltage of these cells to be regulated at most is 2.7V is widely known. While Panasonic NCR18650A (or B) can be discharged down to 2.5V.
So I'm curious why SamSung or LG cell has higher voltage than Panasonic in disharge. I'm sorry to ask another question.

 

[HKJ]

So I'm curious why SamSung or LG cell has higher voltage than Panasonic in disharge. I'm sorry to ask another question.

The voltage (range) is a function of the chemistry, Panasonic did some chemistry adjustment to get the higher capacity and this made it possible to discharge to a lower voltage.

 

[candle lamp]

Thank you so much. :bow:

 

[tobrien]

thanks HKJ!

i personally much prefer the steel bottom plates like this one appears to have since the Surefire springs are so bad with digging in the gold plated ones

 

[ZRXBILL]

Thanks for all you do here. With so many of these new ones poping up I know as soon as I buy the newest & greatest that something much better will come out the next day.:laughing:

Ouch! $25-30 each depending on wether you buy 1 or 2.

 

[roadkill1109]

appreciate the info HKJ! You take out the guess work on our end.

Thanks so much!

 

[HighlanderNorth]

Impressive! and you can buy on ebay too.

Yeah, for $35!!

 

[Erzengel]

German retailers charge "only" 21€ (ca. 26$), while they charge more than 30€ (ca. 38$) for one 3100mAh AW cell. So the Enerpower are more interesting for us European flashaholics because now we don't have any problems with customs, hazmat regulations, shipping bans and so on.

This cell looks really good because it has a higher voltage than the 3100mAh ones. In the past every increase in capacity went together with a decrease in high current stability.

 

[1mT]

Hi!

Could you explain me why blue curve is above red curve after discharge 3 A*h?

Is this measurement error?

 

[jirik_cz]

Protection circuit adds some resistance, that is the reason why the blue curve is under the red curve.

 

[1mT]

Protection circuit adds some resistance, that is the reason why the blue curve is under the red curve.

My question is why the blue curve is above the red curve somewhere.

 

[jirik_cz]

That is just a small difference in capacity of the batteries. Some batches can be better than the others.

 

[HKJ]

My question is why the blue curve is above the red curve somewhere.

One reason can be age of the tested batteries. Batteries are not always new when sold to consumers.
A good example is the Sanyo test I have published a few days ago. The batteries is from 2011.

The capacity will drop depending on how the batteries has been stored.

There can, of course, also be production tolerances between the different batches.

 

[evo666]

I would love to use these batteries in my battery pack to charge my cell phone. I hate going camping without power.
Thanks for the info!