Archive for the ‘NiCd/NiMH Batteries’ Category

We got a pack of the latest generation Panasonic Eneloop Pro AA NiMH batteries with 2500 mAh capacity to check out and see what you can expect from what are considered as one of the best rechargeable NiMH batteries out there. These batteries come pre-charged with solar energy and are low self discharge, meaning that they are capable of retaining up to 85% of their capacity in a year. The Eneloop Pro are great choice for use with devices that require higher current and are also suitable for use in low temperature conditions of up to -20 degrees Celsius with good performance. According to the specifications they should be good for 500 recharge cycles. Looking back a couple of years back when we have tested an earlier generation Sanyo Eneloop XX AA NiMH batteries it seems that things have not changed that much in terms of rated capacity or battery specifications.

The 1.2V AA 2500 mAh Panasonic Eneloop Pro NiMH batteries are rated at minimum 2500 mAh capacity and our discharge tests have shown really good results with very close to that capacity usable at constant current loads of 0.2A and even 0.5A. Going for a higher discharge load of 1.0A and even 2.0A and the batteries still manage to perform surprisingly well at over 2300 mAh usable capacity in both cases. We remind you that these batteries are intended to be used for high drain devices, so we expected to see good performance with higher current loads, but we are also going to be testing them at even higher loads in a separate test to see where is the limit. So it seems that not only the specifications, but also the usable capacity of the newer Panasonic Eneloop Pro is very similar to that of the older generation Sanyo Eneloop XX that we have tested a couple of years ago. The good news is that there is no drop in quality and the new Eneloop Pro rechargeable batteries are still one of the best NiMH AA batteries you can currently get on the market.

The performance of the 1.2V AA 2500 mAh Panasonic Eneloop Pro NiMH batteries in our tests:

– 2472 mAh at 0.2A load
– 2453 mAh at 0.5A load
– 2388 mAh at 1.0A load
– 2322 mAh at 2.0A load

– 3.080 Wh at 0.2A load
– 3.015 Wh at 0.5A load
– 2.870 Wh at 1.0A load
– 2.601 Wh at 2.0A load

It has been a while since we have tested Eneloop batteries, so we were excited to check out what performance we can see from the latest gen Panasonic Eneloop Pro AAA NiMHs. According to Panasonic the BK-4HCDE Eneloop Pro AAA batteries should be able to deliver minimum capacity of 930 mAh, they come pre-charged and are low self discharge, meaning that they should be at retain 85% of their capacity in a year if not being used after a full charge. The Eneloop pro series is intended for high drain devices, meaning that it should handle better under heavier loads, the batteries are also suitable for use in low temperature conditions (-20 degrees Celsius) and are rated at up to 500 recharge cycles (if properly maintained). Of course the Eneloop Pro batteries are made in Japan and with all of the above said they are pretty expensive compared to other competing products, that is why we have high expectations.

The 1.2V AAA 930 mAh Panasonic Eneloop Pro NiMH (BK-4HCDE) batteries manage to deliver slightly more than 900 mAh at lower constant current loads of 0.1A and 0.2A in our tests and that kind of puzzled us, so we have repeated the tests multiple times just to be sure, however without much of a difference… we kind of expected to see the 930 mAh mark covered. Going up to 0.5A load we got at 888 mAh, a really good result and not much lower compared to the lower loads and then, jumping to 1.0A discharge test we see a more significant drop in the usable capacity at 634 mAh. We were a bit disappointed from the results at 0.1A and 0.2A constant current loads, even though the batteries did manage to perform very well at slightly over 900 mAh capacity in the test, we still expected to see a bit more.

The performance of the 1.2V AAA 930 mAh Panasonic Eneloop Pro NiMH batteries in our tests:

– 903 mAh at 0.1A load
– 901 mAh at 0.2A load
– 888 mAh at 0.5A load
– 634 mAh at 1.0A load

– 1.131 Wh at 0.1A load
– 1.103 Wh at 0.2A load
– 1.051 Wh at 0.5A load
– 0.658 Wh at 1.0A load

TATTU is a newer brand of batteries by Gens ace, a popular name for high quality and good priced LiPo batteries among RC enthusiasts. Here we are testing their regular 1.2V AA 2100 mAh TATTU Enerpro NiMH batteries as the company also offers higher capacity 2700 mAh model that we plan to check out soon as well. We have previously tested AA NiMH batteries from Gens ace under their own brand, you can check the results here and compare with the TATTU line if you are interested. The TATTU Enerpro NiMH batteries are low self discharge ones that retain high percentage of their initial capacity oer longer periods of time even when not being used for long time and are rated with up to 1000x recharge cycles.

The 1.2V AA 2100 mAh TATTU Enerpro NiMH batteries are performing quite well in our tests all the way up to the high 2.0A constant load where the usable capacity shows a larger drop. What we are seeing at 0.2A and 0.5A discharge current is a very similar curve and close mAh ratings, though because of the slightly lower voltage at the higher load the gap in the Wh result is a bit larger. What we are seeing here as well as with our previous tests of Gens ace branded NiMH AA cells is that even at 0.2A load (the lowest we use for AA tests) they are performing a bit under their rated capacity, even though their general performance is very good. In both cases you can say the battery rating should’ve been much better if it was with 100 mAh lower that it is being advertised.

The performance of the 1.2V AA 2100 mAh TATTU Enerpro NiMH batteries in our tests:

– 2034 mAh at 0.2A load
– 2026 mAh at 0.5A load
– 1933 mAh at 1.0A load
– 1543 mAh at 2.0A load

– 2.490 Wh at 0.2A load
– 2.392 Wh at 0.5A load
– 2.238 Wh at 1.0A load
– 1.637 Wh at 2.0A load

For more details about the 1.2V AA 2100 mAh TATTU Enerpro NiMH batteries…