Modular lithium-ion battery system for fork lifts

A modular rechargeable battery system for use as a replacement of or as an alternative to a conventional lead-acid battery in a battery-powered industrial forklift truck, said modular rechargeable battery system being adapted to power the battery-powered industrial forklift truck, said system comprising:

• a) a plurality of battery modules, wherein each battery module in said plurality of battery modules includes a positive terminal and a negative terminal, a battery management system including a battery supervisor system (BSS), and a plurality of lithium-ion battery cells, said plurality of lithium-ion battery cells being electrically united with each respective one of said plurality of battery modules to provide a combined electrical potential between the positive terminal and the negative terminal of each respective one of said plurality of battery modules, wherein each of said lithium-ion battery cells is interconnected via wire bonding to a printed circuit board (PCB) on a top side of said lithium-ion battery cells;
• b) a housing having a plurality of compartments, each of said compartments being configured for removably receiving any one of said plurality of battery modules, said housing being sized and adapted to operatively fit within a battery compartment of the battery-powered industrial forklift truck, wherein each of said plurality of compartments includes a pair of power connections for mating connection to the positive terminal and the negative terminal of any one of said plurality of battery modules when said any one is removably received therein;
• c) said housing further comprising electrical conductors and external power terminals, said external power terminals being oriented and adapted for operative connection to the electrical power circuitry of the battery-powered industrial forklift truck, and said electrical conductors having a layout for connecting electric power from the pair of power connections of the plurality of compartments to said external power terminals;
• d) a processor for monitoring the modular rechargeable battery system and for controlling power switches such that operative electrical power is directed through said electrical conductors to said external power terminals, said processor being adapted to direct said operative electrical power to said external power terminals when fewer than all of said compartments have a corresponding one of said battery modules operatively received therein, whereby the battery-powered industrial forklift truck can be provided with operable electrical power when fewer than all of said compartments have battery modules removably received therein;
• e) a battery operating system supervisor (BOSS) module being adapted to grant permission to said BSS to connect or disconnect to at least one bus bar out of multiple bus bars, wherein said BOSS module is further adapted to communicate with said BSS using a controller area network (CAN) via an isolated wire harness, wherein said multiple bus bars include a 0 volt bus bar, a 24 volt bus bar, and a 48 volt bus bar;
• and
• f) with respect to each battery module, said BSS being adapted to:
• 1) monitor operational aspects of said battery module;
• 2) obtain real-time operational information of said battery module, said operational information comprising cell voltage, current, depth of discharge, and temperature;
• and
• 3) compare said operational information with a set of predetermined reference values to determine if there are any operational abnormalities in said battery module, and when one or more abnormalities occur during operation of said battery module, said BSS is further adapted to electronically disconnect said battery module from said at least one bus bar, based at least in part on communication from said BOSS module, wherein said electronic disconnection is operatively performed by a Metal Oxide Semiconductor Field-Effect Transistor (MOSFET) associated with said battery module.