These cells were acquired to test through generous donations for this purpose. I express my gratitude for the support. To avoid any confusion with eGo-type batteries, I use the term "cell" here to refer to individual units such as 18650, 26650, etc.
Disclaimer
The statements, conclusions, and recommendations I present based on these tests reflect my opinion. It is highly advisable to thoroughly research any battery pack you are considering before purchasing.
Testing cells at their maximum limits poses significant risks and should never, under any circumstances, be attempted by individuals who have not extensively studied the associated dangers and how to mitigate them.
A note regarding current ratings and my testing
If the cell displays only one current rating number or explicitly states "max discharging current," it can be inferred that the company claims the cell can handle discharging at that specific current level in any manner, including continuous discharge.
The VTC4 is a high-performing 23A continuous cell, surpassing its 2000mAh rating. They were procured from www.illumn.com and exhibited identical appearance and performance to genuine VTC4 cells. While they operate too hot to be rated at 30A continuous, their temperature at 23A aligns with that of VTC5 and VTC3 cells at their respective ratings. The VTC4 delivers more potent hits than LG HB series batteries but generates more heat.
These tests demonstrate the cell's performance at higher pulsed current levels. If you operate your mod at these levels, please be aware that there is a risk of overheating and potentially venting the battery in case of a malfunction or accidental button press on your mechanical mod.
Sony datasheet ratings and graphs
Please refer to the subsequent post, as I have reached the limit for the number of graphics allowed in a single post.
Authentic Sony VTC4 Battery Specs Reviews
At 10A continuous, the cell achieved a capacity of approximately 1975mAh. This exceptional performance for a 2000mAh-rated cell operating at 10A led me to rate this cell at 2100mAh. This aligns with the nominal capacity rating for the VTC4 like VTC5, and my results are typically consistent with this rating.
The temperature at 15A is continuous and was recorded at 64°C, significantly below the average temperature for a cell operating at its constant discharge rating (CDR).
At 20A continuous, the temperature rose to 77°C, around the average temperature for a cell operating at its CDR.
During 25A continuous discharge, the temperature reached 88°C, significantly exceeding the average temperature for a cell operating at its CDR.
At 30A, the temperature rose continuously to 97°C, which is excessively high to consider this current level as the CDR. This battery cell is not a genuine 30A-rated cell.
At the specified 35A continuous discharge, the temperature rose to 104°C, surpassing my safety limit of 100°C.
I am establishing a CDR of 23A for this cell since its operating temperature at this current level aligns with the average for a cell operating at its CDR. While using any cell near its maximum rated current level causes damage, I expect this cell to exhibit a decent cycle life at 23A.
Pulsed discharges have been included in the tests; however, I still need to define pass/fail criteria for pulse testing. The shots were conducted with a 5-second on/30-second off cycle, down to 2.5V. One chart presents the complete release at each level. In contrast, the other chart provides a close-up view of the initial 5 minutes to facilitate the observation of voltage sag at different current levels.
