Imren 20700 Lithium-Ion Cell Review

Imren has made this nicely wrapped (with yellow and red) 20700 lithium-ion cell, which is capable of 25 amps discharge! Read on for testing!

Official Specs

Here’s a link to the Imren 20700 Lithium-Ion Cell product page.

Size: 20700
Type: IMR/Li-Mn (Rechargeable)
Rated Capacity: 3200mAh
Max Pulse Discharge Current Rating: 40A
Continuous Max Discharge Current: 25A
Approximate Size: 20.4mm diameter by 70.3mm length
Nominal Voltage: 3.7V
Protected: No
Style: Flat Top
Weight: 61.4g
Color: Gold/Red wrapper

Price

You can buy the Imren 3200mah 20700 25A/40A flat top battery at LiionWholesale, for $9.99.

Short Review

I can’t even test up to the full capabilities of these cells, but what I could test, these cells do well. They seem to be very good cells (I’ll support that statement by saying the cells didn’t get over 60 degrees C during the 20A test.)

Long Review

Package

Two of these cells ship in a cardboard Imren box.

A yellow battery packaging box with red and black printed precautions about usage, including warnings against disassembly and heat, and instructions for battery installation. The box also displays barcodes and QR codes.

A yellow box displays red text reading 20700 3200MAH 40A against a wooden background.

Inside that box is the typical plastic flip-open box, suited perfectly to the 20700 size.

A translucent plastic case containing two cylindrical yellow batteries sits on a weathered wooden surface.

Build Quality

There’s a scratch-off authenticity sticker. I tried this, but the URL referenced on the sticker didn’t load for me.

I wouldn’t put much merit in the 40A pulse discharge claim. The 25A claim, however, is likely accurate (I tested up to 20A.)

Nothing much else to say about these. They’re very well wrapped, and the wrapper is very nice.

A yellow cylindrical battery with red text and a barcode is lying on a weathered wooden surface. The text includes “CE,” “RoHS,” and “Made in China.” The batterys terminals are visible on each end.

A yellow cylindrical battery labeled WREN 20700 3200mAh 40A rests on a weathered wooden surface, with sunlight creating blurred patterns in the background.

It’s a flat top cell, of course.

A close-up view of the flat, positive end of a yellow cylindrical battery placed horizontally between two weathered wooden planks.

A close-up, shallow-focus image of a yellow crayon lying lengthwise on weathered wooden boards, with the flat end facing the camera and a small red mark visible on the crayons end.

Size

These are 20.4mm diameter by 70.3mm length.

Bigger than an unprotected 18650 of course. Not all that much bigger than a protected 18650. There are possibly some lights in which this cell would fit already.

Three cylindrical rechargeable batteries of different brands and colors—yellow Nitecore, yellow Imren, and green NCR—are standing upright on a weathered wooden surface.

Three cylindrical batteries are lined up horizontally on a wooden surface, viewed from the end with the terminals facing the camera. The battery casings are yellow, gold, and green. The background is blurred.

Testing

I’ve tried to keep the scales similar, so over time the charts will be generally comparable.

Discharge tests

Even discharging this cell at 20A, the temperature never got over around 60°C. Many (most?) cells are rated to 80°C, so this cell still had headroom.

Capacity

Rated at 3200mAh, and confirmed via the 0.2A discharge curve. The “B” cell reported 3269mAh, in fact, and I only take the cells down to 2.8V.

Energy

Bounce

This is a new section, and I added it just because I think it’s interesting. “Bounce back” is what the cell voltage does when the cell rests after a discharge. Interestingly, after heavy discharge rates, the cell bounces back higher. This corresponds to a discharge amount of less energy, and does mean that there’s energy left in the cell. So if I selected the cell with the highest bounce back (that’s the 20A B cell), and discharged it to 2.8V at 0.2A, I’d still find that there was a lot of energy still in the cell.

Charge test

Power, Constant

Since this is a 25A rated cell, I added a constant 20W curve.

Internal Resistance

Conclusion

This is a great cell for what flashlights are to come. Or, if you do other high-drain activities like vaping, then this cell is a good choice.

Buy these cells for $9.99 here at liionwholesale.com!

Notes

These cells were provided by liionwholesale.com for review. I was not paid to write this review.
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