High-current battery management system

Abstract

An apparatus includes a microcontroller and isolation circuitry including multiple transistor-based switches arranged electrically in parallel to isolate a battery from a load source, wherein the battery is capable of providing high levels of current. The apparatus includes a first buss bar to which first pins of the multiple switches are connected, wherein the first buss bar is to be connected to the battery and a second buss bar to which second pins of the multiple switches are connected, wherein the second buss bar is to be connected to the load source. A microcontroller is programmed to control the multiple switches substantially simultaneously to isolate the battery from the load source upon detecting a predetermined condition.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This application is a continuation-in-part of PCT / US2014 / 40997, filed Jun. 5, 2014, which claims the benefit of U.S. Provisional Patent Application No. 61 / 836,233, filed Jun. 18, 2013, wherein the entire disclosure of both applications are incorporated herein by this reference.BACKGROUND[0002]1. Technical Field[0003]The present disclosure relates generally to the management and protection of batteries, and more specifically to a high-current battery management system.[0004]2. Description of Related Art[0005]Lead Acid batteries are the common battery of choice for starting internal combustion engines (ICE) vehicles. Lead acid batteries are robust in that they can handle a fair number of charge-discharge cycles and can operate in most non-extreme environmental temperature ranges. While they do degrade when over-discharged, the effect is not as drastic as other chemistries. Furthermore, lead-acid batteries are comparatively low cost compared...

AI Technical Summary

Benefits of technology

The present patent is a continuation-in-part of PCT / US2014 / 40997 and claims the benefit of U.S. Provisional Patent Application No. 61 / 836,233 filed Jun. 15, 2014. The patent discusses a high-current battery management system for vehicles that use lead-acid batteries. The technical effects of the patent include the use of lithium iron phosphate (LFP) batteries, which have advantages over lead-acid batteries such as longer cycle lives and higher energy density. The patent also discusses the advantages of other-than-a-lead-acid batteries such as reduced internal resistance, lower weight, and no corrosion or corrosive leakage. The patent proposes a system that can manage the high current demands of starting internal combustion engines and provide the necessary high surge current with much less capacity, resulting in a smaller and lighter battery.

Problems solved by technology

An LFP battery, however, is not as robust as a lead-acid battery when it comes to over-discharging or overheating.

This results in a large amount of excess capacity in the battery bank.

Because LFP requires less capacity to achieve needed cranking amps, LFP batteries have considerably less excess capacity available for other things.

Because the lead-acid battery bank contains a large amount of excess capacity, it can provide this power for a certain length of time.

However, because the LFP battery has much less capacity, there is much less excess capacity to use for such loads.

If the driver were to use the same appliances, they would increase the risk of running down the battery and over-discharging it and increasing the likelihood of a dead battery.

Once over-discharged, an LFP battery degrades much faster than a lead-acid battery, reducing the operational life to less than that of a lead-acid battery.

Additionally, if the battery system were to experience a short circuit, the effect would be even more catastrophic than if a lead-acid battery system short circuits.

The lower internal resistance allows for higher surge currents that can cause much greater damage than seen in lead-acid batteries.

For example, if a cable were to wear through its protective sheathing and contact any metal on the truck, such as the frame or other wiring, the entire battery system could instantaneously become red hot and the metals reach their melting point.

Typically, the result would lead to a fire in the vehicle, either from the battery itself bursting into flames, or other parts of the vehicles become overheated and combusting.

Images