Capacity Test of Varta 2700 NiMH Batteries
European consumer battery maker VARTA, founded in 1904, was acquired by Rayovac (now Spectrum Brands, Inc.) in 2002. Spectrum Brands sells rechargeable NiMH batteries under the Rayovac label in the USA. In Europe and Asia, the Varta brand is still used. I purchased a 4-pack of Varta Power Accu AA 2700 NiMH batteries at Mustafa in Singapore. I measured their discharge capacity using a LaCrosse AlphaPower BC-900 charger. (See my earlier post for tips on using this excellent charger/tester effectively.)
The batteries were found to have a discharge capacity of 2,670mAh +/-1% with an end voltage of 1.45V. Varta claims the batteries have a nominal capacity of 2,700mAh. A previous study of lower capacity rechargeable AA NiMH batteries yielded capacities often well below their nominal capacities. Some credit goes to using the charger/tester in the refresh mode. I noticed that the batteries did not reach maximum capacity until they had been through several discharge/charge cycles.
| Measured Capacity | RSD (4 cells) | %Nominal | End Voltage |
|
2,670mAh |
1 |
98.9 |
1.45V |
Looks like Varta has a winner on their hands. These batteries are close enough to their nominal capacity to earn a 5-star rating from Robert! Kudos to them for honesty.
Important: The LaCrosse BC-900 charger performs [discharge + measurement] in the Refresh Mode immediately after fast-charge termination, which means there’s still a little bit of capacity left that could be filled by extra time spent trickle charging. The capacity could be boosted by an additional 50mAh or more by leaving the battery on tickle charge for an hour or so after the initial charging is finished.
More batteries will be tested and added to the Battery Round-up page.
Robert’s Rating: 
Notes: Batteries were tested using the LaCrosse BC-900 in the ‘Refresh Mode’. I used a charge current of 1,000mA (about 0.4C) and a discharge current of 500mA (about 0.2C). Capacity (C) is measure by discharging the battery to an end voltage of 0.9V under constant load. Batteries were repeatedly discharged and charged until the capacity was stable. The discharge current is similar to that used by the manufacturers to spec their batteries. Sometimes, manufacturers use a lower charge current over a longer time period. IMHO, not practical for routine use. And, the results are not indicative of the real world.
