MonoLith™ Integration Data
Integration Data
Mechanical, electrical, and control interface data for vehicle integration planning. Configuration-specific values are issued at design signoff. The figures below apply platform-wide unless noted.
| Mounting | Four structural rails, two along each long face of the enclosure |
| Rail fittings | Embedded T-nut fittings, positionable at any point along the rail length |
| Lifting / pick points | The mounting rails serve as the pick points — the same feature used for chassis mounting |
| Load path | Distributed along the enclosure long faces, not through discrete corner points |
| Isolation mounting | Supported. Isolator selection, count and placement are customer-defined |
| CAD and drawings | Dimensioned drawings and STEP model provided at design signoff, before build |
Rail-mounted load distribution suits high-vibration and shock applications better than a discrete-point interface. Customers design their frame interface to the rail pattern; no mounting hardware modification is required on the pack.
| Face plate layout | LV/IO at one end, HV connectors at centre |
| Coolant ports | -8AN, on the opposite side from the IO |
| Dimensional layout | Face plate spacing varies with pack width; dimensioned layout provided at design signoff |
| Connectors | Amphenol SurLok Plus for HV, Deutsch DTM for signals. Specified per configuration and stated on the pack nameplate |
| Mating connectors | Supplied with every pack |
| LV signal set | CAN H/L, auxiliary power, wake, contactor feedback, charge enable |
| Auxiliary supply | 12 Vdc nominal, 6–35 Vdc range |
| Isolation monitoring | Continuous. Designed and tested against ISO 6469-3. Thresholds configurable per operating state |
| Grounding | Floating HV with chassis bond at designated points; bonding plan supplied |
Interfacing connections are not all on a single face. The face plate carries LV/IO and HV; coolant ports are opposite. Plan routing and service access for both sides. Exact spacing is configuration-dependent and issued at design signoff.
| Main contactors | Load positive, load negative, and precharge |
| Contactor control | Driven directly by the BMS. Not commandable over CAN |
| Precharge | BMS-sequenced with feedback verification at each state change; sequence aborts on mismatch |
| Controlled break | On shutdown the BMS holds contactors closed until pack current falls below the configured break threshold, or a timeout expires |
| Contactor state feedback | Auxiliary switch per contactor, monitored on BMS I/O and published on CAN |
| Service disconnect | Manual disconnect switch, face-plate mounted |
| Main fuse | Fitted to every pack |
| Fuse coordination | Cell CID → wire-bond redundancy → pack main fuse |
| HV isolation | Designed and tested against ISO 6469-3 |
| Certification path | Cells are UN 38.3 certified. Pack-level UN 38.3 and UL 1973 test programs are customer-elected; EBS supports the client through the process |
Contactors are driven by the BMS rather than commanded over CAN. The BMS opens on its own protection logic without depending on bus traffic, so a CAN fault cannot strand the contactors closed. The VCU commands loads within published limits.
Protection thresholds fall into three categories. Cell operating limits are set by chemistry. Current limits scale with configuration. Operating limits are broadcast live on CAN and derate continuously — these are the values vehicle controls should be designed against. All thresholds are configured and validated during the pack build and locked at delivery.
| Charge voltage | 4.20 V |
| Discharge voltage | 2.50 V |
| Charge temperature | −20 °C to 60 °C |
| Discharge temperature | −40 °C to 60 °C |
These are cell-level limits. Pack-level protection thresholds are configured inside them during the build. Warning and cutoff values for your configuration are issued at design signoff.
Charge is inhibited below the configured low-temperature threshold. Regenerative braking is a charge event and is unavailable on a cold pack — applications operating at low ambient require preheat before regen is enabled.
Cell-level limits are fixed. Pack-level limits are the cell limit multiplied by the parallel count, or the pack hardware ceiling, whichever is lower.
| Parameter | Per cell | Pack limit |
|---|---|---|
| Rated discharge | 60 A | Lesser of cell capability and collector ceiling |
| Rated charge | 25 A | Lesser of cell capability and collector ceiling |
| Standard charge | 5.0 A | 5.0 A × parallel count |
Worked example. A 3S8P aluminium module: cell capability 8 × 60 A = 480 A, collector-plate ceiling 390 A, rated module current 390 A — collector-limited. A copper build raises the collector ceiling. The configuration datasheet states the applicable figure.
| Discharge current limit (DCL) | Broadcast on CAN, derated live |
| Charge current limit (CCL) | Broadcast on CAN, derated live |
| Derating structure | Lookup tables across seven temperature breakpoints and eleven SOC steps, bilinearly interpolated |
| Broadcast interval | 100 ms |
| Command reception | Up to 100 Hz inbound |
| CAN interfaces | Two independent channels, 11-bit and 29-bit identifiers, 125/250/500/1000 kbit/s |
| Message configuration | Up to 20 transmit frames, configured at build and locked at delivery |
| Supported protocols | ISO 14229 (UDS) and CANopen. Frame definitions supplied as a DBC file |
Design controls against the published limits, not against static numbers. A fixed current ceiling is meaningless across temperature — a pack that accepts 200 A of regen at 25 °C accepts none at −25 °C. The BMS interpolates and broadcasts the current limits continuously. A VCU that respects DCL and CCL stays inside the protection envelope at every operating point.
State of charge. The BMS SOC estimate is suitable for monitoring and should not be used as the control anchor for range-critical decisions. Accurate SOC requires open-circuit voltage characterisation at a granularity cell manufacturers do not publish, so the estimate accumulates drift between reference points. For duty cycles with tight energy margins, use coulomb counting with voltage recalibration at rest periods. Terminal voltage under load is not a usable proxy — impedance-driven sag is large relative to the operating window.
| Method | Passive resistive bleed |
| Balance current | 200 mA maximum at 4.2 V per cell |
| Trigger | Enabled by discrete input, typically asserted on charge request |
| Target | Balances toward the lowest cell voltage plus a configured deadband |
| Thermal management | Duty cycle automatically derated as balancing circuit temperature rises |
| Voltage sensing | One tap per series group, all groups |
| Cell voltage accuracy | ±1.5 mV |
| Cell sampling rate | 10 Hz |
| Cell temperature sensing | One thermistor per 24-cell holder |
| Thermistor type | 10 kΩ NTC at 25 °C, β = 3900 |
| Temperature accuracy | ±1 °C from 0 to 40 °C, ±2 °C outside that range |
| Additional sensors | Coolant and cold-plate thermistors at the controller |
| Harness integrity | Open-wire fault detection on all sense leads |
| Pack voltage measurement | Up to 1000 Vdc, ±1 V |
Holder-level temperature resolution is the platform architecture. On a liquid-cooled pack sharing a common plate, a sensor cannot resolve individual cells within a parallel group in any case.
Thresholds are locked at delivery. This is deliberate — protection parameters are validated as part of the pack build and are not field-adjustable. The full threshold table, including configuration-specific current limits and isolation thresholds, is issued at design signoff so vehicle controls can be designed against known values.
| Cooling type | Liquid, structural manifold with per-array flow balancing |
| Flow balancing | Set by manifold design at build. Not field-adjustable |
| Coolant | 50/50 ethylene glycol / water standard |
| Alternative blends | Only where minimum ambient requires it |
| Port type / size | -8AN |
| Flow requirement | Configuration-specific. Scales with array count and duty cycle |
| Heat load | Duty-cycle dependent. Estimate provided at design signoff |
| Differential pressure | Not characterized as a published curve |
| Leak integrity | 24 h dry nitrogen pressure hold, pressure-decay logged to serial number |
| Array proof test | Each array pressure-tested prior to installation |
Coolant. 50/50 ethylene glycol and water is the standard recommendation and the right choice for most applications — it carries more heat per unit mass and pumps more easily than a richer mix. A higher glycol fraction is a trade, not an upgrade: lower specific heat and higher viscosity increase pumping power, most noticeably at cold start. 50/50 protects to approximately −37 °C. Below that, size the blend to your ambient and the pump to the resulting cold-start viscosity.
Flow and differential pressure. Both scale with array count and duty cycle, so there is no single platform figure — a number that fits an eight-array pack is wrong for a single-array pack. We issue a heat load estimate at design signoff; required flow follows from that and your target coolant ΔT. We do not publish characterized dP curves; array length and count vary too widely to generate one per permutation. Standard cooling-circuit acceptance is a pressure proof and leak test on each array before installation — an integrity test, not a flow characterization. Wet flow characterization on a first article is available as a separate time-and-materials program.
Drawings, CAD and STEP model, complete BOM with interfacing connector part numbers, harness pinout, electrical schematic, DBC file, protection threshold values, mass properties and CG. Design is frozen before build begins.
Interface control document including as-built test data, commissioning procedure, lifting and rigging, O&M guide. Mating connectors ship with every unit.
Voltage vs. SOC, DC internal resistance, discharge rate curves, and temperature characteristics are published by the cell manufacturer. Pack values scale by series count — multiply cell values by the series group count for your configuration. We identify the specific cell in the configuration datasheet. Note that pack-level state-of-charge estimation should not be used as a control anchor for range-critical decisions; see BMS Behavior & Protection above.