Spare Battery for MMU-X3R

$23.00

Product Overview

FOURSEVENS 26650 (4000mAh) Rechargeable Li-Ion:
THIS BATTERY WAS DESIGNED TO BE USED IN AND RECHARGED WITH OUR MAELSTROM REGEN MMU-X3R ONLY.
IT WILL NOT WORK WITH ANY 26650 LIGHTS OR THE PREVIOUS GENERATION MMU-X3.

Prometheus In the Wild

Product Details

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.

Storage

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.

Size

26650 (26.5mm x 69mm)
Weight

3.4 Oz
Terminal Type

"Flat Top"
Voltage

3.7V Nominal (4.2V full charge)
Capacity

4000 mAh

Service Life

~500 Cycles
Charge Retention

80% @ 6 Months
Maximum Discharge

8 Amps @ 2C
Electronic/Mechanical Protection

Over charge, over discharge, over voltage, under voltage, short circuit
Where it's made

Customer Reviews