EBL Gold Pro AA NiMH 2800mAh rechargeable low self discharge battery (90% after 3 years) , weighs 28.90g, costs about $1.87 per cell, or 1500mAh per dollar, which relatively inexpensive compared with other brands (Amazon Basic 1290mAh per dollar, Energizer 890 mAh per dollar, Eneloop 460mAh per dollar, POWEROWL 1320mAh per dollar).
Multiple users have showed that the actual capacity of EBL 2800mAh battery is only about 2400mAh. The discharge rates for their tests are probably high to keep the testing time short. Here we measure the capacity by discharging it at a low rate with an 80-Ohm resistor load. We record the voltages over time and calculate the current and integrate to get the capacity. At the average discharge rate of about 15mA, we expect it to take 7-8 days. First it is charged from 1.28V for about 2hrs at 0.3A to 1.440V, which drops to 1.365V after about 1 day and 1.350 after 2days without load. Then the measurements are taken with load. It is fully discharged in about 150hrs and the capacity is 2338mAh. More appropriately, the capacity is 2865mWh. (Or 2388mAh if divided by the nominal 1.2V.) In any case, it is only about 85% of stated capacity, consistent with other user reports. Using the measured capacity, the cost is 1250mAh per dollar, on par with the Amazon Basic. The big brand name batteries are rather overpriced (perhaps they are better in the number of charge cycles or internal resistance).
In a real-world test, it is compared to an Energizer 800mAh AAA NiMH battery (NH12 HR03) in a wireless mouse. The Energizer AAA battery lasted about 1 month and the EBL AA battery lasted two months; tests were run twice and the results were similar. This would imply that the EBL AA is only around 1600mAh, which is a huge disappointment. However, a Panasonic AAA eneloop 750mAh only lasted about half a month, which is a little surprising; if this is accurate, the EBL AA would have 2800mAh as advertised. More testing underway.
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