EV Battery Pack Reconfiguration for 400V and 800V Charging

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Solution Overview

Problem

Existing recharging stations capable of delivering high voltages like 800 V are expensive, and there is a need to utilize these stations efficiently with cost-effective batteries available in the market.

Innovation Solution

A recharging assembly and method that allows connecting batteries in series or parallel configurations using switches controlled by an electronic unit, enabling the electric vehicle to communicate maximum voltage support, optimizing charging with standard batteries and high-power stations.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of time

If high-voltage recharging stations (800 V) are used to reduce charging time, then charging speed is improved, but battery cost increases significantly

Engineering Contradiction:
Improvecharging timeVSAvoidbattery cost
Core Design Contradiction:
Loss of timeVSEase of manufacture

Solution Approach 1:

The patent applies the dynamics principle by making the battery configuration changeable between series and parallel connections based on the recharging station's voltage capability. The battery management system dynamically reconfigures the battery strings: when an 800V HPC station is detected, batteries are connected in series to accept high-voltage charging; when a 400V station is detected, batteries are reconfigured to parallel connections. This dynamic adaptability allows the vehicle to utilize high-power charging infrastructure without requiring expensive 800V-rated batteries, thereby reducing charging time while maintaining cost-effectiveness.

Inventive Principle:
Principle #15Dynamics

2Productivity

If batteries are configured for 800 V charging, then recharging efficiency is improved, but battery compatibility decreases

Engineering Contradiction:
Improverecharging efficiencyVSAvoidbattery compatibility
Core Design Contradiction:
ProductivityVSAdaptability or versatility

Solution Approach 1:

The system dynamically reconfigures battery connections based on the detected recharging station type. The battery management system communicates with the charging station to determine its voltage capability, then automatically switches between series configuration (for 800V efficiency) and parallel configuration (for 400V compatibility). This dynamic switching mechanism ensures both high recharging efficiency when available and broad compatibility across different charging infrastructures.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent changes the electrical configuration parameters of the battery system based on external conditions. By altering the connection topology (series vs. parallel) and voltage levels according to the recharging station's capabilities, the system adapts its operating parameters to maximize efficiency with HPC stations while maintaining compatibility with standard 400V stations, thus resolving the contradiction between efficiency and versatility.

Inventive Principle:
Principle #35Parameter changes

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

Reduces charging time and maximizes the use of high-power stations with standard batteries, ensuring safe and efficient charging without damage.

Implementation Method 1

A battery pack for an electric vehicle includes a first and a second storage battery, each having a positive terminal and a negative terminal. The positive terminal of the first storage battery is connected to the positive terminal of the second storage battery. A switch is connected between the negative terminal of the first storage battery and the positive terminal of the second storage battery.

Methodology Applied
Scientific EffectSeries and parallel electrical connection: Conduction (electrical)

Data Source

PatentEP3687028B1Power supply and recharging assembly and method for an electric vehicle, and electric vehicle comprising the power supply and recharging assembly
Publication Date: 2026.04.15 IVECO SPA
  • EP3687028B1 patent drawingFigure 1
  • EP3687028B1 patent drawingFigure 2
  • EP3687028B1 patent drawingFigure 3

AI summary

A recharging method and assembly to charge an electric vehicle (50) comprising a battery pack (2) including a plurality of storage batteries (2a, 2b, ..., 2i, 2j) having a same nominal charge voltage, the battery pack (2) being connectable to a recharging station adapted to provide a recharging voltage, which his greater than said nominal charge voltage. In an recharging mode of the battery pack, in which the recharging voltage deliverable by the recharging station is smaller than the sum of the nominal charge voltages of the plurality of storage batteries, the storage batteries are connected in parallel to one another, so as to recharge each battery with a recharging voltage equal to the nominal charge voltage. In a different recharging mode, in which the recharging voltage deliverable by the recharging station is equal to o greater than the sum of the nominal charge voltages of the plurality of storage batteries, the storage batteries in series to one another, so as to recharge the series of batteries with a recharging voltage greater than the nominal charge voltage.