NLee the Engineer reviewed:Digital Treasures ChargeIt Battery Station Pro Battery Charger (DRDT-08767)
I already have two 'universal' chargers that can handle AA/AAA/C/D and 9V batteries: the original Rayovac PS3 and the Tenergy TN190. This product (Digital Treasures ChargeIt! Battery Station Pro) attracted my attention since it seems to combine advantages of both PS3 and TN190, plus additional features.
The ChargeIt! Station Pro is a 'Smart' charger that monitors each cell independently, just like PS3 and TN190.
- It is able to recharge alkaline cells (like the PS3) in additional to NiMH and NiCd types
- It has an LCD display panel (like the TN190) that shows individual battery status
- It can recharge high-capacity C & D cell (the PS3 can only handle up to ~3000mAh)
- It has two USB ports with output capabilities of 1A and 2A, respectively (the TN190 only has one 500mA port)
- It accepts 12V input, which means it can be powered from car battery with a simple CLA (cigarette lighter adapter)
The ChargeIt! Station Pro claims to offer "microprocessor monitored charging". This seems to be true based on my observation.
- When a battery of unknown status is inserted, the charger first sends severel current pulses through the battery, presumably to determine the battery status and chemistry.
- For a NiMH cell, the charger starts with ~800-850mA. As the battery gets closer to being fully charged, the charger switches to lower duty cycle to reduce the average current. It stops (LED changes from Red to Green) when a negative voltage slope is detected.
- For a NiCd cell, the charger starts by discharging the cell (LED=Yellow), then follows by a recharge (LED=Red) similar to the case for NiMH.
- For an alkaline cell, the charging current starts at ~80-100mA. As the battery voltage gets higher, the charger switches to lower duty cycle. It stops when battery voltage is high enough (over 1.55V approximately)
- The charger is intelligent enough to detect error conditions such as: wrong battery type selected, reverse polarity, completely exhausted cell (under 0.1V). The Red LED blinks in case of fault.
After playing with this charger for a few weeks, I found it to meet my expection in every aspect. I have used it to recharge different batteries, including C-size NiMH (Tenergy Centura C), AA LSD NiMH (Sanyo eneloop), and ordinary alkaline AA cells (Duracell Copper Top) without problems. The two USB ports also come in handy for recharging my tablets. Unlike the case for TN190, the USB ports of ChargeIt! Station do not turn off when batteries are inserted into the charger.
The only minor concerns I have are:
- The LCD panel needs a backlight
- The charging current of 850mA is too low for high capacity D cells. It will take over 12 hours to fully recharge a 10,000mAh cell.
- The 9V charging port seems to be dumb. It simply charges at 40mA for about 8 hours.
The capability of recharging ordinary alkaline cells is useful when I'm in a pinch. On the other hand, it is important for one to have a realistic expectation. Based on my experience:
- You can never recharge an alkaline cell back to its original capacity. You may get 70% the first time, less with every subsequent charge.
- You can only recharge an alkaline cell a handful of times before its capacity drops too low, or it starts leaking.
- You should use freshly recharged alkaline cells immediately. Don't let them sit on the shelf or inside unused appliances. They may leak if the gas pressure inside is not released soon.
- Do not recharge 9V alkaline battery with this charger. It will either rupture or leak.
I consider this ChargeIt! station to be a better value than the TN190 just for the two USB ports. Consider the added capability of recharging alkaline cells as a bonus, but don't weigh it too much in your purchase decision.