Batteryville
Home Products FAQ About Us Contact Us

Frequently Asked Questions

NiMH Batteries
MH-C204F Charger
MH-C124S Charger

Consumer NiMH Batteries

Q: How much performance improvement can I expect using PowerEX NiMH batteries instead of other batteries on my high drain device like a digital camera?

First: PowerEX NiMH batteries are rechargeable up to 500 to 1000 times. This means you can use the batteries over and over again. If you are familiar with "rechargeable alkaline" (which are significantly lower in price), their life is only about 50 recharges.

Second: PowerEx NiMH batteries are designed for power intensive applications. PowerEx NiMH batteries maintain its high power during most of its usage. In other words, PowerEx NiMH batteries maintain a high and consistent voltage during most of its discharge. On the other hand, for alkaline batteries their voltage drops rapidly when used in a power intensive applications such as digital camera. This explains why you can only take 20-30 pictures using alkaline, while you can take up to 150-200 pictures using PowerEx NiMH. (For those who are a bit more technical, take a look at the discharge curve of a PowerEx NiMH battery)

Third: Capacity counts. NiMH batteries are rated in "mAh", acronym for "mili-ampere hours". This number tells you how long the batteries can last under a certain power consumption. The higher the better for this number. For example, PowerEx NiMH AA batteries are rated at 1700mAh. This means its performance will be much better than the competition's 1200mAh, 1300mAh or even 1400mAh.

Forth (A Bit Technical): PowerEx batteries feature an ultra-low impedance compared to other brands of NiMH rechargeable. A battery with a high impedance is almost like a clogged water pipe: power cannot flow from the battery to your device efficiently. In fact, in a high impedance battery, much energy is lost as heat. Generally speaking, a PowerEx 1700mAh AA battery would have a impedance of 15-17mOhm, while a competitor's battery at the same capacity would have a impedance of 25-30mOhm. The end result? PowerEx battery will perform significantly better than a same-rating competition battery.

Q: What do you mean by "no memory effect" on PowerEx NiMH batteries?

Memory is a type of problem that traditional NiCD batteries would develop. You probably have heard that in order to maintain the life and performance of rechargeable batteries, you have to fully drain the batteries before recharging them. Thanks to "memory free" technology featured on PowerEx NiMH batteries, you can charge them anytime you wish, regardless if the batteries are fully drained or not.

Q: What is the difference between PowerEx NiMH batteries and "rechargeable alkaline" batteries?

Recently the market has introduced a new type of supposedly affordable rechargeable alkaline batteries. However, they do not compare with PowerEx NiMH rechargeable technology. The key difference is that rechargeable alkaline batteries can be recharged up to 50 times. PowerEx NiMH can be recharged up to 500 to 1000 times.

Q: Technically speaking, what makes a PowerEx NiMH battery better than other brands of NiMH batteries?

First: PowerEx NiMH batteries are designed with a ultra thin layer of separator. This allows the substantial increase in capacity.

Second: PowerEx NiMH batteries are designed for power intensive applications such as digital cameras. When subjected to heavy power drain, PowerEx NiMH batteries will continue to perform while other brands may not.

Q: I plan to use the PowerEx NiMH batteries as a backup power. How long will they hold their charge (shelf-life)?

This is commonly referred to as the "shelf life" of batteries. For PowerEx NiMH batteries, the shelf life at room temperature is about 70 to 90 days (for those who are a bit more technical, take a look at the retention curve). If you are seeking for longer shelf life, you may wish to consider alkaline or non-rechargeable lithium batteries, which are commonly used for memory backups.

Q: Explain the various battery symbols and terminologies.

"mAh": Stands for mili-ampere hours. It measure the capacity of the batteries. For example, a 1000mAh capacity means that the batteries will last for 1 hour if subjected to a 1000mA discharge current.

"V": Stands for voltage. It measure the power of the batteries. For NiMH batteries, they are 1.2V. For alkaline batteries, they are 1.5V.

"C": "C" defines the rate at which a battery is charged or discharged. It is the capacity obtained from a new battery subjected to a constant-current discharge at room temperature. For example, draining a battery at 1C means to drain the capacity of a cell completely in one hour. Likewise, draining a battery at 0.2C means discharge a battery in 5 hours. For nickel-metal hydride cells, the rated capacity is normally determined at a discharge rate that fully depletes the cell in five hours, or 0.2C.

Q: How often should I condition my batteries?

Generally speaking, NiMH batteries do not suffer from the "memory effect" and thus do not require conditioning. Nevertheless, to ensure top performance, conditioning is recommended at once for every ten charges. For Nickel Cadmium (NiCD) batteries, conditioning is recommended every time you charge your batteries.

Q: How many times can I recharge my batteries?

The number of times you can recharge your batteries will depend on the operating parameters, such as drain rate, battery care, etc. In general, under desirable condition, NiMH can last up to 500 recharges. In best condition, NiMH can last up to 1000 recharges.

Q: Can I leave my batteries in the charger until I need to use it?

When used with a overnight charger (such as the Maha MH-C124s) or a rapid charger with automatic termination (such as the Maha MH-C204F), NiMH batteries can be left in the charger for an extended period of time without leakage, explosion, or deformation. However, do not store the batteries in the charger if it is not necessary. Always store charged batteries in a cool location.

Top

MH-C204F Q & A

Q: What do the LED lights mean on the MH-C204F?

Indicator (LED) Condition Meaning
Red Rapid Charging
Green Charge Complete
Yellow Flashing Conditioning

 

 

 

 


When the green lights are shown, the batteries are ready for usage.


Q: What is conditioning?

The conditioning feature on the MH-C204F basically rejuvenates your batteries by first draining them and then charging them. By using this feature, your batteries will perform at their highest standards. Conditioning is also used to eliminate the memory effect which NiCD batteries exhibit.

Q: How often should I condition my batteries?

For Nickel Metal Hydride (NiMH) batteries, conditioning is recommended at once for every ten charges. For Nickel Cadmium (NiCD) batteries, conditioning is recommended every time you charge your batteries.

Q: The batteries get warm when I charge them. Is this normal?

When charging NiCD or NiMH rechargeable batteries, they do increase in temperature substantially due to internal resistance. Thus, the batteries may feel warm when the charge is completed. According to specification, most NiMH batteries, including Maha, may heat up to 131 deg F or 55 deg C during a rapid charge. This can certainly feel hot to some individuals.

Q: Can I leave my batteries in the charger until I need to use it?

For most NiMH batteries, including Maha rechargeable batteries, can be left in the charger for an extended period of time without leakage, explosion, or deformation. However, do not store the batteries in the charger if it is not necessary. Always store charged batteries in a cool location.

Q: Can I use the MH-C204F in my car?

Since the MH-C204F runs on 12V DC, you can use it in the car provided that you have a cigarette lighter adapter (Maha Part Number: MHS-DC-124). Make sure that your vehicle is supplying 13.8V or below. Some trucks may have 24V. In addition, never plug in the charger while you are starting your vehicle.

Q: Can I use my MH-C204F to charge "Renewal" or other rechargeable Alkaline batteries?

No. The MH-C204F is only compatible with NiCD and NiMH style rechargeable batteries. Charging "Renewal", other alkaline batteries, or non-rechargeable batteries, may result in damaging the charger or even fire.

Q: When I insert the batteries into my charger, there are no lights whatsoever. What could be wrong?

If no indicator is displayed, check your power source. Make sure it is plugged in correctly into a wall outlet with matching specification listed on the wall adapter. If you continue to experience difficulty, it may be possible that the wall adapter have failed. In that event, contact Maha's customer service at 1-800-376-9992 for assistance.

Top 

MH-C124S Q & A

Q: How long exactly is needed to charge my batteries?

The charge time varies with the battery capacity. You are recommended to remove the batteries at the suggested time table below. Keep in mind that since the charging speed is so slow, going over a few hours will not harm the batteries.

Battery Type
Recommended Charging Time
PowerEx 1700mAh AA NiMH
29 hours
PowerEx 1600mAh AA NiMH
27 hours
PowerEx 1500mAh AA NiMH
25 hours
MAHAcell 1550mAh AA NiMH
26 hours
PowerEx 650mAh AAA NiMH
11 hours
Generic 1400mAh AA NiMH
23 hours
Generic 600mAh AA NiCD
10 hours

 

 

 

 

 


 


 


Q: Do the green LED lights turn off when the batteries are charged?

The green LED lights on the MH-C124S simply indicate that you have a completed circuit, and that the batteries are being charged. The lights do not turn off (and do not indicate that the batteries are fully charged) until you take the batteries out of the charger. Remember to take the batteries out after the prescribed time.

Q: Can I use my MH-C124S in the car?

Since the MH-C124S runs on 12V DC, you can use it in the car provided that you have a cigarette lighter adapter (Maha Part Number: MHS-DC-124). Make sure that your vehicle is supplying 13.8V or below. Some trucks may have 24V. In addition, never plug in the charger while you are starting your vehicle.

Q: Can I use my MH-C124S to charge "Renewal" or other rechargeable Alkaline batteries?

No. The MH-C124S is only compatible with NiCD and NiMH style rechargeable batteries. Charging "Renewal", other alkaline batteries, or any non-rechargeable batteries, may result in damaging the charger or even fire.

Q: I was reading the features on the MH-C124S battery charger. It says : Charges either 1,2,3 or 4 Battery Cells at a time Could you explain a little more?

Yes, you can charge just 1 battery without placing any other batteries in the charger if you wish. Or you can charge 2,3, or 4 batteries at a time as this charger has 4 totally independent charging circuits. As a matter of fact let us say you need to charge 4 batteries and 2 are "AAA" and 2 are "AA". No problem, the MH-C124S will charge them all at the same time. It makes no difference where you put them.

Q: What is the most batteries the MH-C124S battery charger will charge at one time?

The MH-C124S battery charger is designed to charge no more than 4 BATTERIES at a time. Attempting to charge more than 4 batteries will cause severe damage to your charger.

Top

NiMH Battery Discharge Curve

This chart indicates the discharge curve of PowerEX NiMH batteries in various discharge rates. The discharge is measured in the unit of "C", or capacity. 1.0C means 1.0 x capacity of battery (i.e. If the battery is 1,200mAh, then the discharge rate is 1,200mA or 1.2A), and 0.2C means 0.2 x capacity of battery. As you can see, PowerEX NiMH batteries remain at a high voltage even near the end of the cycle. PowerEX NiMH batteries will hold full voltage (1.2v/cell) up to 80-90% of usage (varies on discharge rate).

Top

NiMH Battery Retention Curve

This chart indicates the retention curve, or the ability that a battery can hold a charge. At different temperature, PowerEX batteries have a different retention capability. You can leave the batteries on the shelf for an extended period of time without loosing all charged capacity.

discharge.gif (3464 bytes)

Top

Home Products FAQ About Us Contact Us