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KeepPower 18350 (2 pcs)

Shipping Warning

Postal regulations do not permit shipping Lithium Ion batteries outside of the U.S. unless your order also contains a flashlight. If you are shipping outside the US please add a flashlight, or remove the Lithium Ion battery.

KeepPower 18350 (2 pcs)
KeepPower 18350 (2 pcs) KeepPower 18350 (2 pcs)
Product Overview

KEEPPOWER 18350 (1200 mAh) Rechargeable Li-Ion:
WORKS WITH: Prometheus Delta/Alpha Shorty (and other 18350 lights)

Product Details

Here is what separates IMR cells from standard Li-Ion:

IMR cells are a specialized Li-Mn (Lithium Manganese) chemistry specificaly designed for high-drain applications. While they excel at delivering massive discharge rates, their capacity is much more limited than a Li-Ion of the same size. The KeepPower 18350 is the highest capacity IMR battery in this size, but it will only deliver 20 minutes of run-time on the highest power setting in an Alpha flashlight. Can't have everything right? That's also why the are sold in pairs :)

NOTICE: Using a "standard" (non-IMR) battery in an Alpha Shorty or Delta light may cause a fire and explosion. They cannot handle the massive current drain the light demands.

Recharge early and often!

Do not run rechargeable batteries until they are completely empty (when the light shuts off on its own). Doing so will trip the protection circuit and render the battery inoperable. The Foursevens Flex Charger and Xtar VC2/VC4 chargers are normally able to reactivate a tripped battery; however, best practice is to recharge early and often. Fully discharging the battery causes long term damage to the cell.


ALWAYS store batteries in a protective case that will prevent short circuits. NEVER put bare cells into a pocket, bag, or drawer. A short circuit will lead to an uncontrolled release of energy...otherwise known as a ball of molten lava.

Do batteries have a "memory" effect I should worry about?
NO. Modern rechargeable batteries (Li-Ion or NiMh) do not have any memory effect. It's best practice to recharge early and often. In fact, fully depleting a battery will damage it and reduce the overall capacity.
what is the shelf life of a charged battery?
Generally speaking, all our batteries will retain 80% of their charge after six months. People worry about this more than they should. Modern batteries hold a charge for a long time. Just charge them and put them away properly. You should charge batteries once a year. Putting them in the fridge is also a myth. Don't do it.
Does heat or cold have a negative effect?
Li-Ion and NiMh batteries can be operated in sub-freezing temperatures. However, a cold battery will deliver less capacity (run time) than expected. Batteries should ALWAYS be at room temperature before charging. Charging a frozen battery can permanently damage the cell and lead to an internal short circuit. In a Li-Ion battery this can cause a fire. Most batteries can tolerate heat up to about 104F/40C. You should never leave a light (or any device) inside a car and exposed to direct sunlight.
Should I leave batteries on my charger all the time?
NO. It's best practice to remove batteries from the charger once they are fully charged. It also depends on the quality of your charger, but again, best practice is to remove the batteries. Some low quality chargers can create a risk of fire.
Can I install batteries backwards to prevent accidental activation?
NO! Back in the day people would install batteries backwards in a light for storage and to prevent the light from turning on by accident. You should NEVER install batteries backwards in electronic devices.
impact resistant wrapper
A special heavy-duty wrapper material resists cracking, unlike standard battery wrappers. This does make our batteries slightly thicker than comparable cells.
Premium cells
We use only top quality cells from reputable manufacturers. Obviously we recommend our own batteries because we can guarantee the quality, and our lights are designed specifically to work with these batteries. NEVER (ever) purchase Li-Ion batteries on eBay because of rampant counterfeiting and sub-standard quality. These batteries can be dangerous and lead to fire and/or explosion. Saving a few bucks isn't worth burning down your house with your family inside.
  • Size
    18350 (18mm x 35mm)
  • Weight
    1.1 Oz each
  • Terminal Type
    "Flat Top"
  • Voltage
    3.7V Nominal (4.2V full charge)
  • Capacity
    1200 mAh
  • Service Life
    ~500 Cycles
  • Charge Retention
    80% @ 6 Months
  • Maximum Discharge
    10 Amps @ 8C
  • Electronic/Mechanical Protection
    Not available with IMR chemistry (beware of short circuit)
  • Where it's made
Customer Reviews
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