What does LiHV stand for?
LiHV stands for Lithium-polymer high voltage batteries. There are also referred to as high voltage LiPos and have been around for quite some time. These batteries are somehow similar to the standard LiPo batteries but whose main aim is to provide higher voltage rates than LiPos. When a typical LiPo battery is charged, it can reach heights of up to 4.20V which is technically quite higher than other lithium-ion types. However, with the LiHV batteries, one is capable of expanding this voltage to 4.35V per cell safely. This provides LiHV batteries with larger energy capacities and lower voltage sag per cell as compared to LiPo batteries.
What are the advantages of LiHV battery and LiPo?
The following are some of the advantages that LiPo batteries have to offer:
Lithium-polymer batteries incorporate a polymer electrolyte without using an outer protective packing made out of metal. This makes the battery weigh less.
2. High capacity
Lithium-polymer cells are of similar sizes to steel shell batteries with their capacities being about 10% more than that of an aluminum battery. This enables the cells to supply more power to devices for extended periods while charging.
3. Customizable shape
With the price being within a standard range, manufacturers need not worry about the limits set upon them when it comes to producing LiPo batteries in the various shapes that are of the right economic size. These batteries can increase or decrease in thickness depending on the consumer's demands, developments of new battery technologies, and various other factors.
4. Enhanced safety
The lithium-ion battery has an aluminum composite packaging incorporated into the structure different from the liquid metal case of other batteries. Thus, in the event of hazards during battery failure, the other types of lithium batteries are prone to fires and explosions, unlike lithium-polymer cells.
5. Efficient discharge properties
Lithium-polymer batteries include a gel-like electrolyte as compared to the liquid electrolyte found in other battery types. The gel-like electrolyte provides a larger discharge platform for these cells as well as ensuring they have an effective discharge rate and flow.
6. Low internal resistance
Lithium-polymer batteries have a low internal resistance that can go below 35 m Ω. This significantly reduces the battery power consumption for many devices and also extend their standby period. This property makes LiPo batteries suitable for high-end devices and a much better alternative for replacing other battery types such as NiMH cells.
LiHV batteries also have close to the same characteristics as lithium-ion cells, and they include the following:
1. Higher-end voltage
LiHV batteries are designed to provide a higher voltage as compared to LiPo cells in general. These batteries are incorporated with a unique matrix of chemical composition that enables them to reach voltage hights of up to 4.35V as compared to lithium polymer's 4.20V. This gives your devices more power as compared to LiPo cells, such as in the case of RC models.
2. Higher energy densities
LiHV batteries provide higher energy densities as compared to LiPo cells. This means that they can supply large amounts of power at once during flight time, for example, of your RC models. The quality makes them a suitable partner for use in high-end devices. Instead of LiPo cells, it requires more significant amounts of power supply.
3. Increased energy capacity
As compared to LiPo cells, LiHV batteries have a much larger energy capacity. This makes them capable of lasting longer than the standard LiPo batteries. The beneficial part of this feature, in RC planes, for example, is that it will give you longer runtimes or fly times.
4. They are lighter
LiHV batteries are much lighter as compared to other battery types despite having large energy capacities. While other battery types make their devices more cumbersome, LiHV cells don't add much weight and are therefore suitable for RC models such as drones.
5. It is safe
LiHV batteries come installed with all the safety features that are recommended to prevent various hazards that affect lithium-ion batteries. These safety measures help prevent overcharging, over-discharging, and over-current situations that may pose many risks. Unlike lithium-ion cells that can explode, LiHV batteries are safe from such explosions.
There are various disadvantages that these two battery technologies face, and they include:
LiPo batteries provide better efficiency rates for energy as compared to other lithium-ion types. With a more substantial capacity, high energy densities, and better safety measures, LiPo batteries tend to be more expensive than other lithium-ion cells. They cost almost double the price of lithium-ion cells.
2. No standard shape
There is no standard shape that is used to identify lithium-polymer batteries. These cells can be manipulated into any shape during production, depending on the consumer's demands. They are also mainly manufactured for high volume user market thus come in many shapes and sizes.
3. Less recharge life
LiPo batteries support a much lesser recharge life as compared to lithium-ion cells. Their recharge life can only accommodate about 300 to 400 relatively low cycles.
4. Requires special care
LiPo batteries need to be monitored during charging and discharging periods.
Since these cells were designed to give a safe and higher voltage than LiPo batteries, they don't come cheap. Their purpose was to provide larger energy densities and capacities than lithium-polymer cells and can thus be considered better alternatives. However, LiPo batteries are costly, and thus, it is expected that LiHV batteries being a better version should be even more expensive.
2. Less stable
LiHV batteries have been proven to be less stable as compared to LiPo cells. Seemingly exceeding the voltage limit per cell by a small amount could severely damage the receivers or transmitters in the entire battery.
What are the differences between LiHV battery and LiPo?
Apart from having a higher-end voltage as compared to standard LiPo cells, LiHV batteries reduce the chances of puffing as were present in LiPo batteries. They also provide a lower internal resistance than LiPo cells and higher capacities. Generally, LiHV batteries were designed to be better versions of LiPo cells.
LiHV batteries may be considered better than LiPos in many different ways. However, I would advise you to stick to the standard LiPo batteries as their better versions have not been widely idolized. The future holds excellent opportunities for it, however.