UCANPOWER UHB series of high-voltage energy storage batteries has attained a lot of attention and favor from many customers since launched. Most of attentions depend on the module-level active balancing technology which as with one part of UCANESS core technology allows UHB product to run efficiently, safely and durably.

Today let’s take a look at the reason why the high voltage battery system shall be balanced for management? What are the advantages of the active balancing technology developed by UCANPOWER?

We have to learn that the high-voltage battery system is composed of a number of battery modules connected in series, and when the modules connected in series are gathered side by side, there is a discrete phenomenon before we try to get into the balancing question.

Discrete Phenomenon

Discrete phenomenon of Li-ion battery packs refers to the difference in voltage, charging capacity, internal resistance, cycle lifetime, self-discharging rates and other parameters of the cells with same specification, and such difference will become larger after forming into a battery module. It highlights when compared with the consistency and uniformity of the battery pack, the higher the level of self-discretization, the worse the consistency and uniformity.

The battery modules connected in a series receive the same charging and discharging currents in a high-voltage battery system, but due to the existence of discrete phenomena, there are differences in the capacity of each battery module and the charging and discharging capacity of the entire battery system depends on the smallest unit of single battery, which results in “barrel principle”. The battery module with smaller capacity will reach the charging and discharging depth value at first when the process starts, which in turn restricts the charging and discharging capacity of other batteries in the system. The battery system cannot reach to full charge or discharge for a long time, losing part of its capacity, creating a “barrel principle” in the capacity, resulting in an inaccurate SOC (State of Charge) for the whole system and a decrease in the depth of discharge and a reduction in operating efficiency. The battery has been polarized after running for a long time, and the usable capacity of which will be further reduced.

Let’s take the marathon as a example, where the runners are all on the same starting line when it begins, but afterwards they pull away from each other during running.

In addition, the impact of temperature on the cycle lifetime of lithium batteries conforms to the “Arrhenius equation”. Research indicates that lithium battery temperature increases by 10℃ every time the degradation rate doubled, the cycle lifetime of the battery cell decreased by nearly 50%. Therefore, in the running process of series-connected lithium battery module, it will also show differences after a period of cycling even if the other parameters are identical as the two ends of the temperature is lower than the middle part.

Hence, the non-consistency or discrete of the battery pack is an inevitable performance of battery operating, and which will lead to a decline in the capacity of the whole set of batteries, and give rises to a decline in the service life, depth of the cycle, and a reduction in running efficiency. As a result, the balancing technology of the battery is particularly significant, which enables to keep good consistency among modules.

UCANPOWER MODULE LEVEL ACTIVE BALANCING TECHNOLOGY

UHB series of high-voltage battery is a expandable modular battery system independently developed by Ucanpower, taking lithium iron phosphate cells with excellent charging and discharging performance, as well as features like safety and reliability. The system provides PV energy storage solutions for three-phase residential and small scale of commercial and industrial scenarios when matching with the UHC storage inverter. UHB series of high-voltage batteries have already obtained CB and EMC certifications, and widely installed in the European market.

UHB series of high-voltage battery system takes module-level active balancing technology, which realizes real-time self-balancing in the whole process of charging and discharging modes, reduces the voltage difference among each battery modules, and makes the charging and discharging cycles of the battery modules close to the same, which effectively prolongs the service life of the battery system, guarantees the depth of battery cycles, and ensures the stable and efficient running of the battery system!