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Ultrafire 2500mAh Rechargeable Protected Li-Ion Batteries 18650

Ultrafire 18650 2500mAh 3.7V Protected Lithium Ion (Li-ion) Button Top Battery - Bulk (ULTRAFIRE-18650-2500-PTD)
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Item #:ULTRAFIRE-18650-2500-PTD
Product Review:
Regular Price:$16.95
Sale Price:$7.95 & Free Shipping
With Orders Over $50!
This item has been discontinued.
Ultrafire 18650 Protected Rechargeable Lithium Battery

Detailed Description:

Protected 18650 2500 mAh rechargeable 3.7 volt battery - charge with the Ultrafire Multi-Battery charger.

The advantage of this cell is that it features a button top making it particularly compatible with many flashlight applications.

Rechargeable Lithium batteries are rapidly becoming a very economical way to lower the operating costs of Lithium-Powered flashlights. We offer a number of different options in order to meet any rechargeable needs. These are Protected batteries.

These fully protected cells simplify usage with their integrated PCB. Perfect for your single cell application these cells are not for pack building as doing so will defeat the PCB protection which is matched to the correct voltage on a single cell. If you are building a pack please choose one of our other cells and the appropriate PCB.

Features and Benefits:
  • Unique and New! With integrated PCB Protection!
  • Lithium Ion 18650 cylindrical rechargeable batteries
  • Internal PCB protection prevents under-voltage at 2.5V and over-voltage at 4.25V.
  • Unique PCB design and patent pending.
  • Higher energy density and lower weight than other types rechargeable batteries
  • Manufactured under ISO9001-2000 to assure quality
  • Battery tested based on International Electrotechnical Commission (IEC) standard to ensure capacity, quality and life time
  • Lighting or other device needing 3.7V power
  • Building portable power device needing high energy density and low weight
Product Specifications:
  • Capacity: Nominal: 2500 mAh, Minimum: 2250 mAh
  • Internal PCB protection prevents under-voltage at 2.5V and over-voltage at 4.25V.  UNIQUE INTERNAL PCB!
  • Dimensions:
    • Diameter 18.3+/-0.5 mm
    • Height 66.5+/- 0.5mm
  • Weight (Typical) Approx. 46 g
  • Nominal Voltage: Average 3.7V
  • Cut-off Voltage: 2.5V
  • Internal Impedance: less or equal to  180  milliohm (with PTC)
  • Cycle Performance: 90% of initial capacity at 400 cycles
  • Cycle life: > 500 cycles
  • Charge: Current = 0.5C mA Voltage = 4.2 V End Current = 0.01 mA
  • Discharge: Current = 0.5C mA End Voltage = 3.0V

NOTE: 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. We are not responsible for damage if there is any modification of the batteries/chargers in any form or shape (including pack making). We are not responsible for any damage caused by misuse or mishandling of Li-Ion batteries and chargers. We only recommend using Lithium Ion rechargeable batteries with a control circuit (protection PCB) to assure safe charge, discharge, etc, use of lithium ion batteries without a protection circuit is potentially hazardous

More Information:

Ultrafire 18650 2400mAh button top protected rechargeable lithium ion batteries are a high-quality, reasonably-priced battery option for today’s lithium powered flashlights. These cells are 3.7V and feature PCB protection for ease of use. As such, these batteries should only be used in single cell environments and not as part of a pack.

Battery Size:18650
Battery Capacity:2500mAh
Battery Chemistry:Li-Ion Rechargeable
Battery Voltage:3.7V
Battery Terminal Type:Button Top
Battery Shelf Life:3 Years
Warranty:Battery Junction 30-Day Warranty
Return Policy:Battery Junction Return Policy
Country of Origin:CN
Ultrafire 18650 2500mAh 3.7V Protected Lithium Ion (Li-ion) Button Top Battery - Bulk (ULTRAFIRE-18650-2500-PTD)
3.5 Stars based on 6 Review(s)
Fall River, MA
4 Stars
I would recommend this item to a friend.

Excellent battery for the price
January 12, 2015
Does what is expected. Would purchase again.

Will Plan
The South
4 Stars
I would recommend this item to a friend.

Rechargeable is the way to go!
December 3, 2014
Purchased a set of two initially to try them out. First set about a year ago, then 4 more recently. First set have been charged 10-12 times and have been reliable. I replace batteries with "fresh charged" ones about every month. So far no complaints, except the charger only charges 2 at a time.

3 Stars
I would recommend this item to a friend.

Great Budget Lithium Battery but not for Mission Critical Equipment
November 7, 2014
I bought a few of these batteries about 4 years ago as some cheap spares for domestic use in some old torches (flashlights for you guys). I was aware they may not be the best quality like many of the "high end" lithium batts I have but wanted to give them a try in some hand me down torches I was giving to the kids to use. I have had to "reset" the protection circuit a couple of times after they failed (ran too low on charge or overheated and would not recharge) which is fine if you know what you are doing.
Cheap and expendable (I am not going to cry if I loose one or have to throw it away)
DO NOT USE IN MISSION CRITICAL EQUIPMENT !!!!! but fine in domestic environment. Great for use in the "dog walking light" but I am not going to use in any Search & Rescue equipment.

4 Stars

Very good for the Money
December 17, 2013
I\'m using these in a Nitecore SRT6 after initial charging 8 days ago, with a voltage reading of 4.06 and using it off & on since then, I then set it on full mode 930 lumen or Turbo for 6 minutes, then checked the Voltage with a reading of 3.86. My Inova tester also put a mild load on all batteries. I think these batteries are very good. They are not truly Round .012 out of round average, Widest at the top wear the protection device is located.. But every battery I\'ve checked is about as bad, as little as .006 on Alkaline (EverReady & Duracell). Most devices allow for this.

John Collins
1 Stars

Exceedingly Poor Quality
May 4, 2013
I have previously used your Tenergy 18650 2600mah and UltraFire 18650 3000mAh batteries with excellent results. But two of the newly-purchased Ultrafire 2400mah batteries will completely lose their charge in 2 days just sitting, while the remaining one, freshly charged overnight, runs my tactical flashlight for less than half the time of one of my much-used, nearly worn-out Tenergy 2600 batteries that I bought the Ultrafire 2400\'s to replace. In short, they are worthless, useless, and I cannot recommend them to anyone. I am now buying 3 more Tenergy 18650 2600mah batteries to replace these disasters.

Dan C.
5 Stars

Reliable & Excellent
September 8, 2010
This 18650 is excellent. It\'s a real workhorse. It does what it\'s supposed to do. The price Battery Junction sells it for is excellent.

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