Page 123 - Toucpad robotics C11

Characteristics
Low Energy Density: Significantly heavier and bulkier than Lithium-ion batteries for the same amount of stored energy.
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High Current Delivery: Capable of providing very high surge currents for short periods, which is good for starting
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large motors.
Robust and Reliable: Known for their durability and ability to withstand rough handling.
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Relatively Inexpensive: One of the most cost-effective battery technologies per unit of energy stored.
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Voltage Stability: Maintain a relatively stable voltage during discharge until they are nearly depleted.
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Applications in Robotics
Heavy-Duty Industrial Robots: Used in large industrial Automated Guided Vehicles, forklifts, and older, stationary
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industrial robots where weight is less of a concern and robust, inexpensive power is needed.
Large Outdoor Autonomous Vehicles: Sometimes found in larger, slower-moving outdoor robots or research
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platforms where budget is a primary constraint and space/weight are not as critical.
Backup Power Systems: Often used as backup power for robotic systems or charging stations, similar to
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Uninterruptible Power Supplies (UPS).
Solar-Powered Robots: Used in conjunction with solar panels for energy storage due to their durability and cost-
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effectiveness.
Advantages
Low Cost: The most economical rechargeable battery option, making them attractive for budget-constrained
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projects or larger applications.
High Current Delivery: Excellent for applications requiring a burst of power (high cranking amps).
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Robust and Tolerant: Less sensitive to overcharging/over-discharging compared to Lithium-ion, within reasonable
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limits. More tolerant to a wider range of operating temperatures.
Mature Technology: Well-understood and proven technology with established recycling infrastructure.
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Safe: Less prone to thermal runaway and fire compared to Lithium-ion, generally considered safer if properly handled.
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Disadvantages
Heavy and Bulky: Their low energy density means they are significantly heavier and larger than Lithium-ion batteries
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for the same energy capacity, limiting their use in mobile or aerial robots.
Lower Cycle Life: Typically have a shorter lifespan in terms of charge-discharge cycles compared to Lithium-ion.
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Sensitive to Deep Discharge: Repeated deep discharges (draining the battery completely) can significantly reduce
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their lifespan.
Slower Charging: Generally take longer to charge than Lithium-ion batteries.
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Maintenance (for flooded types): Flooded Lead-acid batteries require periodic topping up of distilled water and
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ventilation due to gas emission during charging. Sealed types reduce this.
Memory Effect (for some types/usages): Can exhibit a form of “memory effect” or reduced capacity if not fully
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charged or if left discharged for long periods.
Summary of Comparison

Feature Lithium-ion Batteries Lead-Acid Batteries
Energy Density High (Lightweight, compact) Low (Heavy, bulky)
Cost Higher Lower

Cycle Life High (Many charge/discharge cycles) Lower (Fewer cycles)
Power Density High (Good for rapid acceleration) High (Good for surge currents)

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Electrical and Control Systems