Panasonic NCR18650B 3400mAh 3.7V
Protected IMR Li-ion Battery - Button Top Batteries
The most technologically advanced 18650 Panasonic batteries currently available.

These are the batteries recommended to be used with
our NEW cordless underwater LED flounder gigging lights.

Back to Home Page | 03/28/15 Update to this page

PCB Protected 3400mAh Button Top rechargeable Li-ion Panasonic Industrial NCR18650B 3.7V Cell. Made in Japan.
These are top of the line, highest capacity, highest quality 18650 batteries currently available.

Current prices on eBay range from $22 to $26 for a pair.
You will need FOUR of these batteries... See photo to the right....

These PANASONIC batteries outperform all other 18650 batteries to date. If you search eBay for 18650 batteries, 98% or more of what you will find are JUNK batteries with outrageous claims as to their power rating. There are some very good products made in China, but the majority of China made batteries available on eBay are a waste of your money and you cannot TRUST the capacity ratings to be correct. False capacity ratings are only there as a marketing scheme. Do not buy any of the batteries under the name of UltraFire or ****Fire. Any battery listed showing a CAPACITY rating above 3400mah is false advertising.

IMPORTANT: You will also need a high quality battery charger capable of charging FOUR batteries at once. One such charger is the Efest LUC V4 charger that features charging modes of 0.5A, 1A, or 2A.

Typically the chargers cost ... Please read the REVIEW at the link below and then Search eBay for current pricing.

Here's a link to a good review of the Efest charger and some other battery chargers... click here.

Important NCR18650B Protection Features:

Over current protection - 8 Amp cut off
Over discharge protection - disconnects when voltage reaches 2.5 VDC to protect the battery
Over charge protection - stops charging when it reaches 4.2 VDC
Double short circuit protection
Over heat protection
Heat resistant layer to make this power cell safer to use.
Conventional BUTTON top design....
Note: Flat top batteries will not work as they are not stackable in a series.

NCR18650B Specifications:

Original Panasonic (Industrial) products, Made in Japan
Feature IMR "Safe Chemistry" construction**
Capacity: 3400mAh (Min 3250mAh)
Charging volt: 4.2v
Max charge current 0.7C 2A
Recommend discharge current 1C 2.9A
Discharge Termination Voltage: 2.5V
Protection kicks in : 2.75v and 4.2v
Over-Charging / Draining at 4.2v / 2.75v
Protected: Yes.....Protection Circuit installed
Button Top design
Weight : 47g
Size 18.50mm x 69.5mm (Larger than non-protected, flat top batteries)
The voltage of full charge & empty condition is 4.2v & 2.75v respectively

IMPORTANT.....THESE BATTERIES MUST BE RECHARGED WITH A LI-ION CHARGER. DO NOT USE A NIMH CHARGER.

**IMR batteries are often referred to as "safe chemistry" batteries as they are a different chemical composition to standard Li-Ion batteries, with lower internal resistance, and should be able to deliver a higher current while maintaining their capacity and avoiding thermal build up. Use special caution when working with Li-ion cells, they are very sensitive to charging characteristics and may explode or burn if mishandled. Make sure the user has enough knowledge of Li-Ion rechargeable batteries in charging, discharging and assembly before use. Always charge in/on a fire-proof surface. Never leave charging batteries unattended.

These Panasonic NCR18650B batteries may be purchased on eBay or other internet vendor websites. Search for Panasonic batteries, search for "NCR18650 protected", or search for other brands with "protected 18650 IMR batteries". Do NOT buy IRC batteries... They need to be IMR construction..... and .... must be of BUTTON TOP design. Do not buy FLAT top batteries.

Panasonic NCR18650B are among the best available. Currently the 3400mAH is the highest capacity produced. You can also use the Panasonic batteries rated at 3100mAH. While not quite the same power capacity, the price will be a little less. Just be sure they are "protected" IMR.

Samsung should be of good quality as well as Sony, ORBTRONIC, KeepPower, NiteCore, Fenix, or Efest. You will also find some these brands/vendors selling batteries under different brand names that use the NCR18650B as the basis for their battery. These should be OK, but do your own research.


SUMMARY: Pretty much without exception, if the battery price is CHEAP, you are not getting good quality, so don't waste your money. On eBay and Amazon.com there are LOTS of cheap 18650 batteries, don't be tempted to buy them. Put your money towards QUALITY batteries.

IMPORTANT: We only recommend using Lithium Ion rechargeable batteries with IMR chemistry, button top design, and a control circuit (protection PCB) to assure safe charge, discharge, etc.

Hopefully you have read all the information above... Should be pretty obvious that quality batteries are extremely important. If you have ANY questions, please do not hesitate to call to discuss. (phone number is on homepage)

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Update - March 27, 2015

The information below is from www.BudgetLightForum.com
and is assumed to be accurate.

Protected Panasonic NCR18650B come in 3 form factors:

1. Button tops.
Example

The top is raised to facilitate stacking, small diameter, and has 2 vent holes
The bottom is flat,
The length is about 69.5-69.6 mm

The primary purpose of these is to stack them in flashlights such as those with a battery extension tube.

2. Raised tops (and bottoms).
Example

The top is raised and larger in diameter than button tops and has 3 vent holes,
The bottom is raised too to facilitate stacking,
The length is about 70 -70.1 mm long as reported by BLF members (My measurement through thin plastic is 70.5mm)

These are most versatile and are designed to work in flashlights that use stacking and those that do not. The disadvantage is that they are longer than the rest and the flashlights must be designed to accept them.

3. Flat tops (and bottoms).
Example

The top is only slightly raised as these are not designed for stacking, the largest in diameter, and has 4 vent holes....The bottom is flat.....Their length is shorter than the batteries above.

These are designed to work in 1 battery flashlights or mufti-batttery flashlights that do not stack batteries.

(Reference is to Battery Chargers)
Opus BT-C3100/Opus BT-C3400 will charge 18650 Batteries up to about 71 mm long.