The main differences between NiMH and NiCd batteries are capacity, recharge time, and the number of charge/discharge cycles.
The NiCd battery is cheaper but has a lower storage capacity. The NiMH battery can store more power, so it will run for longer before needing to be charged again.
If you’re concerned with cost and want to save money on your solar light setup, the NiCd might work better for you.
However, if you have an issue of running out of charge in the middle of the night or don’t mind spending a little bit extra upfront, then go ahead and invest in a NiMH battery because it will last much longer between charges.
NiCd Batteries
NiCd batteries are a type of electric battery. NiCd stands for nickel-cadmium.
The positive electrode is cadmium, which allows for a higher energy density than nickel-metal hydride batteries (NiMH). NiCd’s provide both high power and long life in devices such as portable tools, toys, flashlights, and clocks.
NiCd batteries have good cycling and shelf life capabilities but they will deteriorate quickly under high loads. This makes them less useful in applications where high current pulses are required.
The electrodes in a NiCd battery consist of porous metallic cadmium grids into which the active material, nickel hydroxide, is deposited.
Pros
- Highly reliable and provide many recharge cycles
- Provide consistent power throughout the life of the battery, even as its charge depletes
- Have a long shelf life (up to 20 years) if charged regularly
Cons
- Bulky and heavy for their small energy output compared to other types of rechargeable batteries
- Tend to be expensive and can only handle a limited number of recharging cycles (typically less than 500) before the capacity drops below half of their original charge (this loss in battery life is known as the “memory effect”)
- Cannot supply high peak currents such as those needed by digital electronics like personal computers
- Tend to not be environmentally friendly due to cadmium pollution when disposed of or discarded
NiMH Batteries
NiMH stands for nickel-metal hydride, which is a type of rechargeable battery that has no cadmium involved in its construction or disposal. They are also known as Ni–MH batteries and have been regulated by the IEC as IEC R20 on their terminals.
They provide extremely long life in devices such as portable tools, toys, flashlights, and clocks. They have a nominal voltage of 12 volts and range from 600 to 3000 mAh capacity, but some types can go up to 5000mAh.
NIMHs can provide up to 40% more power than their NiCd counterparts!
Pros
- Low in self-discharge, meaning they retain their charge for a much longer time than other rechargeable battery types
- Can be recharged over 1000 times before losing capacity and provide up to 40% more energy than NiCd batteries
- Don’t require priming or conditioning unlike other battery types
- Have an average capacity of 2500 mAh with larger sized ones offering up to 3500 mAh
- Can be used with any type of device that uses a rechargeable battery and is the preferred choice for low drain devices such as remote control toys, flashlights, or smoke detectors
Cons
- Quite expensive compared to other battery types
- They are also larger in size than some other rechargeable batteries, which makes them more difficult for smaller devices like watches or calculators
NIMH batteries have many advantages over nickel-cadmium batteries, including environmental friendliness and no memory effect. Some of the main reasons they are considered green are because they are not made with any lead or cadmium.
They also have a higher capacity and can hold their charge longer, along with being able to be recycled more easily than other types of batteries. NiMHs are used in all sorts of products, from cars to big power tools, that need a lot of juice for efficient operation.
All these benefits make the NiMH battery one of the most popular rechargeable batteries on the market today!
What Are The Differences Between NiCd And NiMH Batteries?
- NiMH batteries charge more slowly but hold a higher capacity. This means that the battery can run longer before needing to be recharged than NiCd batteries. They also generally perform better at low temperatures, making them an excellent choice for remote controls and other devices used outdoors.
- NiMH batteries are cheaper than NiCd batteries. They also do not suffer from the “memory effect” that NiCd batteries are prone to developing, so they can be recharged even if you haven’t fully drained them first.
- NiMH batteries are more environmentally-friendly compared to NiCd batteries. They can be recycled and do not contain any toxic heavy metals such as cadmium or mercury. However, they still have the same general disadvantage in regards to environmental pollution when being manufactured in terms of energy consumption.
- NiCd batteries generally last longer than NiMH batteries. The trade-off is that NiMH batteries hold a much higher charge and recharge more quickly, making them better to use in high drain devices like digital cameras.
- There is also a difference in the number of charge/discharge cycles. NiCd batteries have a higher number of charge/discharge cycles, which makes them better for low drain devices like remote controls. You can also run them longer before needing to recharge. NiMH batteries have fewer but longer-lasting cycles, making them better suited for high drain devices like digital cameras because they hold more charge and recharge quicker than NiCd.
- There is also a difference in memory effects. NiMH batteries do not suffer from the memory effect that can reduce NiCd battery performance over time.
The memory effect is a phenomenon in which the first part of a battery’s capacity to be used decreases as usage continues because it becomes filled with data telling it how much energy has already been released.
For example, a fully charged rechargeable battery will lose its capacity to store energy if it is only discharged up to the 50% mark before being recharged.
NiCd batteries are particularly susceptible to memory effects because they have a floating charge system. This means that once they are fully charged their voltage drops slightly as stored power is used and then rises again when more power is applied.
Even if NiCd batteries are only partially discharged before being recharged, they will have lost some power.
NiMH Vs NiCd For Solar Lights: Which Is The Better Option?
As you can see, there are many pros and cons to each type of battery chemistry. So, which should you choose? Let’s take a look at the applications of each type of solar light.
NiCD is often used in cheaper products like:
- children’s toys
- game controllers
- also, work well with high-drain devices like flashlights
The main advantage of NiMH batteries is that they do not have the “memory” problem associated with other rechargeable battery chemistries. NiMH batteries also have a much longer cycle life than NiCd, so they are great for solar lights.
NiMH batteries are typically used in:
- larger applications like solar lights
- electric vehicles
- commercial standby power
If you’re looking to pick up cheap solar lighting that is good enough for your kids, we recommend going with NiCd. If you’re looking for a solar light that is going to last, then NiMH is your best bet. NiMH is best for solar lights that are going to be used frequently!
Conclusion
NiCd and NiMH are two different types of batteries that can be used in solar lights. Both have their own pros and cons, so it is up to you and your individual needs to decide on which battery type is best!
It is important to do your research before buying any batteries, but NiMH is a great choice for solar lighting purposes due to the lack of harmful chemicals in its composition.
We hope this article has been helpful in answering any questions you may have had about the differences between these two power sources for your outdoor solar lighting!
