Online switching circuit for series-parallel connection of storage battery pack

Abstract

An online switching circuit for series-parallel connection of a battery pack is characterized in that batteries in the battery pack are connected through a bidirectional linkage switch group, wherein the bidirectional linkage switch group can be a mechanical bidirectional linkage switch group, multi-group synchronously-controlled bidirectional contact electromagnetic relays or solid-state relays or transistor electronic switching circuits. Multiple combination switches in coaxial linkage or synchronously-controlled relay groups are correspondingly adopted according to different quantities of single batteries in the battery pack, series-parallel connection of the battery pack is instantaneously switched by changing the turning direction of an intermediate contact and a moving contact in a combination circuit of the battery pack. By the aid of the switching circuit, the battery pack can be connected onto electric equipment in a series connection manner and is used for supplying high-voltage output for the equipment, and the battery pack can also be connected onto charging equipment in a parallel connection manner so that the charging equipment can perform identical equalizing charge for each single battery with optimum voltage required by each single battery, and the single batteries in the battery pack can be kept consistent.

Description

Technical field [0001] The invention relates to a circuit of an input-output connection mode of a battery pack. Background technique [0002] At present, there are many technical problems that need to be solved urgently in the practical application of battery packs: the consistency and service life of battery packs have always plagued the development of the battery industry, and there is no substantial and thorough solution so far. The more batteries connected in series, the higher the monomer scrap rate. So, how can we solve the consistency problem of the battery pack? Through many years of experiments, we found that lead-acid batteries have a common problem. When charging, they are used as energy storage devices to store electricity, and when discharging, they are used as power supplies to supply external power. However, when the discharge voltage is lower than a certain value, they will become loads and consume batteries. Therefore, when the battery pack is discharging,...

AI Technical Summary

Problems solved by technology

So, how can we solve the consistency problem of the battery pack? Through many years of experiments, we found that lead-acid batteries have a common problem. When charging, they are used as energy storage devices to store electricity, and when discharging, they are used as power supplies to supply external power. However, when the discharge voltage is lower than a certain value, they will become loads and consume batteries. Therefore, when the battery pack is discharging, if one of the cells lags behind first, it will consume the power of the entire battery pack, causing the discharge voltage of the entire battery pack to drop below the end-of-discharge voltage set by the controller and fail to work. and terminate

The reason why the battery pack has poor consistency and poor balance is not that the battery manufacturer has poor technology and lax control, but because of the inevitable result of the series combination of batteries. For example, the commonly used 12-volt battery is six monomers connected in series. , sealed in a battery case, it is impossible to take effective measures to thoroughly control the parameters of the consistency balance between each monomer

A set of 48-volt battery packs is usually composed of eight 6-volt or four 12-volt batteries in series, but the dynamic balance between 8 or 6 series batteries does not reach 2 volts in a set of batteries. The parameter consistency among the 24 monomers is balanced, so it will inevitably lead to one or several 12-volt batteries with poor internal balance as the number of uses increases.

To completely solve the problem of consistency of battery packs, only by starting from the essential principle of the battery - 2V single cells, and only by connecting the battery packs in parallel can the consistency and balance of the parameters of each single cell in each battery pack be ensured, and the whole pack can be completely avoided. Only the occurrence of single-cell premature lag caused by the accumulation of undercharge and overdischarge of lagging single cells in the battery can ensure the extension of battery life. However, when the batteries are connected in parallel, they can only provide a total voltage output of 2 volts, which cannot meet the power consumption requirements at all. equipment needs

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