Custom Battery Packs for AGVs and Mobile Robots
24V and 48V LiFePO4 and NMC packs for AGVs, AMRs and legged robots. Most robot batteries do not die of bad cells; they die of integration: heat trapped in the middle of the pack, resistance in the interconnects, charging in the cold and discharge limits set too deep. We design those out.
Robot platforms we build for
Reference packs are starting points. Envelope, connector, BMS protocol and current limits are normally adapted to your chassis and drive controller.
| Platform | Typical voltage | Was treibt das Design an? | Referenzpakete |
|---|---|---|---|
| Warehouse AGVs and AMRs | 24V – 48V | Opportunity charging between tasks, lift-motor peaks, telemetry to the fleet manager | 51.2V 50Ah AGV (1C, CAN/RS485) 24V 90Ah AGV |
| Heavy-load AGVs, tuggers and stackers | 48 V | Long shifts, high continuous current, fit in an existing battery bay | 51.2V 315Ah |
| Outdoor UGVs and inspection robots | 48 V | Sealing, vibration, wide temperature range | 48V 100Ah wasserdicht |
| Quadruped robots | Project-specific, often 48V | Pulse capability and safety outdoors; LFP usually preferred | Individuelles Design |
| Humanoid robots | Projektspezifisch | Mass and volume budget; NMC 21700 usually preferred, with strong thermal control | Individuelles Design |
Sizing an AGV pack for opportunity charging
An AGV battery does not need to last a full shift if the robot can charge between tasks. Sizing for the longest gap between charging opportunities, instead of the whole shift, often halves pack size and cost. What it cannot shrink is the peak current: lift motors and acceleration set the minimum power capability regardless of energy.
- Average power over a working period, logged from the robot:
500 W - Longest gap between charging opportunities:
2 h→ energy per gap1.0 kWh - Usable window: 10% SOC buffer at the bottom and 3.0V/cell cutoff, plus 20% ageing margin → rated
1.0 ÷ (0.9 × 0.8) ≈ 1.4 kWh - Peak power, lift motor plus drive:
4.5 kW→4,500 ÷ 51.2 V ≈ 88 A - Charge acceptance at a 15-minute dock stop at 0.5C on 50Ah:
25 A × 51.2 V × 0.25 h ≈ 0.32 kWh
Five integration errors that halve AGV battery life
Cell quality is rarely the root cause. These five integration mistakes can cut rated cycle life by 50 to 70 percent. Full analysis: Warum AGV-Batterien frühzeitig ausfallen.
| Failure mode | Was geschieht | Typical integration | How we design it |
|---|---|---|---|
| Thermal gradient | Centre cells run 5–8°C hotter and age about 1.5× faster; the BMS cuts off while healthy cells still hold charge | > 8°C spread | Airflow channels and thermal pads to the chassis, < 3°C spread |
| Interconnect resistance | Under-torqued busbars add 80–150 mV of sag; false low-voltage shutdowns with 20–30% charge left | Hand-tightened | Torque-verified busbars (5 Nm), cables sized for peak current |
| Cold charging | Charging LFP below 10°C plates lithium on the anode and permanently loses capacity | Charge at any temperature | Heaters and BMS charge block until cells reach 15°C |
| Deep discharge | Cutoffs below 2.8V/cell grow internal resistance and can halve cycle life | 2.5V/cell, 100% DoD | 3.0V/cell cutoff, 10% SOC buffer |
| Vibration | Floor joints and uneven surfaces fatigue cell tabs; erratic voltage readings | Starre Montage | Damped tray, foam compression, flexible internal busbars |
Designing for peak loads, not average loads
Robots reset when bus voltage drops below the controller’s undervoltage lockout during a burst. The cause is DC resistance: at 200A, a pack with 10 mΩ of total loop resistance drops 2V and turns 400W into heat inside the enclosure. On a 24V robot with an 18V logic threshold, a cold start plus acceleration is enough to reboot it.
For systems above 100A peak we target total pack resistance below 2 mΩ at beginning of life, because cell resistance rises about 30% at 0°C and about 40% by end of life. That target drives the build: high-power cells where the duty cycle needs them, oxygen-free copper busbars instead of nickel strip, ultrasonic welds instead of spot welds, and parallel strings that share the current. Details: Hochentladungsbatteriedesign für mobile Roboter.
| Robot action | Peak power | Average power | Peak-to-average ratio |
|---|---|---|---|
| Humanoid: Gehen, um zu sprinten | 3,5 kW | 800 W | 4.4× |
| Humanoid: Erholung im Herbst | 4,2 kW | 600 W | 7.0× |
| Vierfüßler: gebundener Gang | 2,8 kW | 600 W | 4.7× |
| Vierfüßler: Sprunglandung | 6,0 kW+ | 500 W | 12×+ |
Representative figures for legged robots. A pack sized only for average power will collapse during these transients. More: Batterielösungen für hohe Transientenlasten in vierbeinigen und humanoiden Robotern.
BMS and integration
- Kommunikation
- CAN and RS485 as standard, so state of charge, temperature and fault flags reach the robot and the fleet manager. Having the interface is not the same as matching your protocol: send the protocol document and we confirm the registers before quoting. See Optionen für das Batteriekommunikationsprotokoll.
- Fast current sensing
- Motor stalls last 20–50 ms. For high-rate robots the BMS needs to sample fast enough to see them and tell the drive controller to reduce torque before a hard cutoff.
- Charging contacts
- Charge current, voltage and the handshake with your docking station agreed up front, including temperature-gated charging for cold stores and freezer aisles.
- Chemistry choice
- LiFePO4 for most AGVs and outdoor robots: safety, cycle life and low resistance. NMC for humanoids and mass-critical designs. Trade-offs: lithium-ion vs LiFePO4.
- Standards
- Industrial lithium packs are typically assessed against IEC 62619, with UN38.3 for transport. Which reports cover your exact design is confirmed at quotation.
Lieferzeit und Bestellmenge
Aus einer gesperrten Spezifikation: Proben in 12–15 Arbeitstagen, wenn die Zellen auf Lager sind, 20–25, wenn die Zellen beschafft werden müssen; Produktion in 30–35 Werktagen. Ab dem ersten Designgespräch: etwa 4 Wochen für ein finales Design ohne neue Werkzeuge, 8–12 Wochen für ein typisches kundenspezifisches Projekt, 14–18 Wochen, wenn eine Zertifizierung vorgesehen ist. So funktioniert jede Phase: Entwicklungsprozess für kundenspezifische Akkupacks Und unsere Fertigungskapazitäten.
AGV and robot battery questions
Why does my AGV’s battery percentage drop suddenly during lifts?
LiFePO4 or NMC for a mobile robot?
Does an AGV battery need active cooling?
Can the robot work in cold stores?
Can you build to our existing battery drawings?
Weiterführende Literatur
Send your robot’s battery requirements
Ein Techniker antwortet mit Fragen oder einem Konfigurationsvorschlag. Je mehr von dieser Liste Sie teilen können, desto schneller können wir ein Angebot erstellen:
- Robot type and payload
- Nominal voltage and drive controller model
- Logged current profile, or average and peak current
- Charging method and gap between charges
- Battery bay dimensions and weight limit
- Betriebstemperatur, einschließlich Kühlhäusern
- Kommunikationsprotokoll
- Jahresvolumen und Zielvorgaben