![]() Like I said it is not 100% accurate but it gives you a good picture of the battery state of charge. Then use that data to compare with the battery under test. The more data you have, the more accurate. Overall, these 2025 Lithium Coin 3-volt Batteries are a great one to keep on hand as you never know when you might need them. packaging which is really great Also, these batteries are made with zero mercury. All you need is to record the pulsed battery voltage profile as it is discharged. Battery: 2 CR2025 Lithium, Required, Included. Next, have a good read at this patent and the circuit is easy to make with a microprocessor. In Figure 2, you can clearly see the voltage curve of the voltage drop V2 when pulsed discharge as the battery charge depletes. Here is another very good PDF on state of discharge when lithium coin cell is pulsed discharge. The internal resistance of a lithium coin cell behaves differently when it is pulsed discharged. The datasheet you linked doesnt even show you graphs of pulsed discharging characteristics. However, recent studies suggest the actual shape of the curve and pulsing intervals could generate spec sheet data far more efficiently than previously: ĭear mojo-chan It seems that your so called 'research' is only limited to contant load discharging. These are often done for QC checks in production, not for calculating the spec sheet data. Pulsing at 400 ohms or less and insure Vo > 2.5 works for most new cells, of acceptable quality. At 1kohms or greater, the curves are ~ flat and will be mostly useless, however you can still detect drops in voltage in > 1kohm loads with a 6.5 digit DMM but the bigger issue is internal resistance vary by the quality of the battery, so detecting small changes depends highly on the quality of manufacture. To test a 'new' cell's capacity insure pulse loading is at or above the load line of the curve. ![]() Pulsing must be sufficiently fast to avoid wasting a primary cell, an eload is preferred. For Button cells, you need to pulse test with 400 ohms or less. ![]() Yes, because those loads are for estimating applications, not for capacity, their test loads are in kiloohms. Note, a similar thing can be done to high mAH cells like 123A, but its far more risky to do given the battery's higher capacity so you need to know what you're doing fairly clearly. You can't really say what its quantitative mAH is, but you can say the tested battery is less than brand new. For a steady output, the lower the pulse voltage is the more worn it is. A new cell will drop its output voltage and remain flat, but a very worn cell can also be pushed to the knee of the curve for an easy diagnosis and may not stabilize and drop continuously. A good cell will not drop below 2.5V at room temp under load, its easily seen in a typical discharge curve for 2016. A better test is load the cell briefly with 400 ohms and check the voltage simultaneously. If the battery is at end of life, the discharge voltage will be in or past the knee of its discharge curve unloaded, so the lower it is past 3V the more worn it is. What others have said is true, but if you are doing it for a qualitative quick test of a simple CR2016 the answer is yes.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |