Valve regulated sealed lead-acid batteries (VRLA) are a common type of battery widely used in communication, power, UPS and other fields. The following is a detailed analysis of its advantages and disadvantages:
advantage
High sealing and safety
Adopting a sealed structure, the electrolyte is adsorbed in the ultrafine glass fiber partition without overflowing, and can be installed in any direction (such as horizontal or vertical), suitable for space limited scenarios.
Internally equipped with the principle of oxygen recombination, the oxygen generated by the positive electrode can be reduced to water at the negative electrode, reducing water loss and eliminating the need for regular fluid replenishment, resulting in low maintenance costs.
No acid mist spills during normal use, environmentally friendly, and does not require specialized ventilation facilities.
Easy to maintain
No need to frequently check the electrolyte level, density, or add distilled water, saving manpower and time costs, suitable for unmanned scenarios such as base stations and data centers.
Low self discharge rate (monthly self discharge rate ≤ 3% at room temperature), long storage time, and can be idle for a long time in backup power scenarios while maintaining power.
Good reliability and stability
The float charging life is relatively long. In an environment of 25 ℃, the float charging life of high-quality products can reach 10-15 years, making it suitable as a long-term backup power source.
The charging and discharging performance is stable, and it can work normally in a wide temperature range (-20 ℃~50 ℃) (but high temperature will accelerate the decay of life).
Cost-effective
Compared with lithium batteries, lead-acid batteries have lower costs, especially in high-capacity energy storage scenarios where their advantages are significant.
Mature technology, perfect production process, stable market supply, abundant spare parts and maintenance resources.
Strong high current discharge capability
It can provide high current discharge in a short period of time (such as starting motors, emergency power supplies) to meet the instantaneous high power demand.
disadvantage
Low weight to energy ratio
The energy storage capacity (energy density) per unit weight is relatively low (about 30-50Wh/kg), and it is heavier than lithium batteries at the same capacity, making it unsuitable for weight sensitive scenarios such as electric vehicles.
Short cycle life
The deep cycle life (at a discharge depth of 80%) is usually 300-500 times, much lower than that of lithium batteries (over 1000 times), and the replacement cost is high in frequent charging and discharging scenarios.
Excessive discharge or insufficient charging can significantly shorten the lifespan and require a charge discharge management system.
The environmental temperature has a significant impact
The optimal working temperature is 20-25 ℃. High temperature (such as above 40 ℃) will accelerate the drying of electrolyte and corrosion of electrode plates, and the service life can be shortened by more than 50%.
The discharge capacity decreases significantly at low temperatures (for example, the capacity may drop to 60% of the rated value at -10 ℃), and insulation measures are needed.
There is a risk of pollution
Harmful substances such as lead and sulfuric acid, if not handled properly after disposal (such as illegal dismantling), can contaminate soil and water sources. It is necessary to strictly follow the environmental recycling process.
If environmental protection measures are not in place during the production process, lead dust and acid mist pollution may occur.
Large volume
Low energy density leads to a large volume (capacity density of about 60-100Wh/L), occupying a lot of space and being unfriendly to scenarios with limited installation space.
Slow charging speed
Conventional charging takes 5-8 hours to fully charge, while fast charging may cause the plates to sulfide, affecting their lifespan and not suitable for scenarios that require rapid energy replenishment.
Summary and Application Scenarios
Applicable scenarios: communication base station backup power supply, power system relay protection, UPS uninterruptible power supply, emergency lighting, low-speed electric vehicles (such as electric bicycles) and other scenarios that do not require high weight and volume requirements and require long-term float charging backup.
Alternative solution: In high energy density and long cycle life demand scenarios (such as electric vehicles and high-end energy storage), lithium batteries (such as lithium iron phosphate and ternary lithium) are gradually becoming mainstream, but lead-acid batteries still dominate the mid to low end market due to cost advantages.
When using, attention should be paid to controlling the ambient temperature, avoiding overcharging and overdischarging, and cooperating with reasonable maintenance strategies to maximize its service life and performance.
