AGV Power Systems

Battery Technology Comparison

Battery Type	Full Charge Time	Cycle Life	Runtime vs Lead-Acid	Charging Overhead
Lead-Acid	5+ hours	300-500 cycles	Baseline	~30% of work time
Pure-Lead AGM	~30% of work time	Better than standard LA	Similar	~30% of work time
Lithium-Ion / LFP	2 hours full; 10-20 min opportunity	4,000-6,000 cycles	3x	~10% of cycle time
Li-ion with wireless	Same as Li-ion	Same	Same	~8% of cycle time

LFP (lithium iron phosphate) is the dominant new-build chemistry. 60% lighter than equivalent lead-acid. ~10x longer cycle life.

Charging Methods

Opportunity Charging (Contact Poles)

• Vehicle charges during idle periods at defined charging stations
• Li-ion: 10-20 minute charge adds several hours of runtime
• Lead-acid: requires near-full discharge first; opportunity charging degrades lead-acid cells
• Traditional contact pole connection (mechanical contact)

Wireless / Inductive Charging

• Contactless power transfer via inductive pad
• Up to 95% energy transfer efficiency
• Enabled by smart battery management system (BMS) with data communication
• Overhead: ~8% of cycle time for Li-ion with wireless

Manual Battery Swap

• Operator swaps depleted pack for charged pack
• Near-continuous vehicle operation (~98% availability)
• Highest labor cost
• No specialized charging station required per vehicle

Automatic Battery Swap

• Robotic system exchanges batteries without human intervention
• Eliminates labor cost of manual swap
• Higher infrastructure investment

Charging Method Selection Logic

Condition	Recommended Approach
High utilization (>80%), Li-ion	Opportunity charging (wireless preferred)
High utilization, lead-acid	Manual or automatic swap
Low-medium utilization	Opportunity charging at end-of-shift or break
24/7 operations, maximum uptime	Automatic swap or wireless opportunity

Rule: match charging approach to vehicle utilization rate and available idle time. No universal answer - requires project-specific analysis.

Battery Management System (BMS)

Modern AGV batteries include an integrated BMS that:

• Monitors cell voltage, temperature, and state of charge
• Enables data communication with the fleet management system
• Controls charging current to prevent damage
• Required for wireless charging compatibility

Fleet-Level Power Planning

• Li-ion allows fleet to run on fewer vehicles due to lower charging overhead (10% vs 30%)
• Lead-acid 24/7 fleets typically require 1.3-1.5x the vehicles needed for a single shift to account for charging rotations
• Wireless opportunity charging simplifies lane design (no manual swap station footprint)
• Charging stations must be included in fleet management traffic routing