Test/Review of Windyfire IMR18350 850mAh (Red)

Windyfire IMR18350 850mAh (Red)

Official specifications:

  • Type of Battery: IMR 18350/850mAh
  • Size(mm): 18mm(Diameter) x 35mm(Length)
  • Positive Shape: Button top
  • Weight(g): 22±1g
  • Nominal Voltage: 3.7V
  • Nominal Capacity: 880mah(0.2 C Discharge)
  • Minimum Capacity: 850mah(0.2 C Discharge)
  • Discharge Cut-off voltage: 3 V
  • Standard Charge: 0.4 A /4.2V
  • Maximum charge current: 0.85A
  • Quick Discharge Current: 0.85 A
  • Max Discharge Current: 4 A
  • Initial Impedance : Max:65mOhm
  • Cycle Life: 310times: discharging capacity>85%, 510times: discharging capacity>60%
  • Temperature Characteristics: -10°C/0.2C >80% Capacity; 20°C/0.2C =100% Capacity;60°C/0.2C >95% Capacity
  • Charging Time: Standard charge : 5-7hours, Rapid charge : 2-3hours
  • Operating environment: Charging, 0°C ~ 45°C ; 65±20%RH, Discharging, -20°C~60°C ; 65±20%RH
  • Storage environment: Temp(-20°c -35°c) / Relative humidity (45-75%)

This is a IMR cell, but only with moderate high current ability, but good capacity.

The cell does fine up to 3A load, but at 5A load it loses significant capacity.


These batteries has good performance at moderate loads and I will rate them acceptable.

Notes and links

The batteries was supplied by Windyfire 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
Comparison to other LiIon batteries

thanks for the review hkj :slight_smile:

850mAh at 3A looks about as good as it gets for 18350!

seems to me that for a xp-g2, xm-l2 etc two of these might supply buck regulated 5A at emitter for around 12 mins, with driver losses. longer than a 18650?

i wonder what prices these cells will come out at…

The combination of current and capacity is good, but you can find lower capacity that can deliver more current.

Nice capacity for such a little cell.

I cannot help but wonder what these retail at and from where since the recent battery shipping troubles. Time will tell though.

Thank you for the review.

It's good to see more IMR 18350 reviews. Thanks for the review HKJ!

Windyfirecom had these for $1.68, and AW IMR’s for $1.99 !
but only payment methods are Western Union, China Bank AND
no free shipping ( shipping cost to be emailed, and DHL was default over HK post)

Boo :frowning: