Power and life extension of battery-ultracapacitor hybrids

Abstract

The performance of a battery-ultracapacitor hybrid power source under pulsed load conditions is analytically described using simplified models. We show that peak power can be greatly enhanced, internal losses can be considerably reduced, and that discharge life of the battery is extended. Greatest benefits are seen when the load pulse rate is higher than the system eigen-frequency and when the pulse duty is small. Actual benefits are substantial; adding a 23 F ultracapacitor bank (3 7 PC10 ultracapacitors) in parallel with a typical Li-ion battery of 7.2 V and 1.35 A hr capacity can boost the peak power capacity by 5 times and reduce the power loss by 74%, while minimally impacting system volume and weight, for pulsed loads of 5 A, 1 Hz repetition rate, and 10% duty.

On the performance of commercial supercapacitors as storage devices for renewable electrical energy sources

“…Good performance is also manifested by supercapacitors at negative temperature of -30 … -40 o C whereas for batteries such temperature is not recommended.. Also, supercapacitors can deliver for short time electrical energy at significantly higher power than batteries. This advantage and charging / discharging in a short time makes possible usage of hybrid supercapacitor-battery units in applications including renewable energy power systems, [6][7]. Other advantages of supercapacitors in comparison with batteries are related to maintenance and impact on environment.…”

Tam Elektri̇kli̇ Araçlar İçi̇n Özgün Bi̇r Enerji̇ Yöneti̇m Si̇stemi̇ Uygulamasi

“…Bu alandaki çalışmalar pasif, yarı aktif ve aktif enerji yönetim sistemleri olmak üzere üç başlık altında toplanabilir [16]. Pasif hibridizasyon, sürüş süresini [17] veya güç ve sistem ömrünü [18] arttırmak amacıyla süperkapasitör ve bataryaların birbirlerine ve yüke paralel bağlanması temeline dayanmaktadır [19]. Yarı aktif hibritler iki kaynağın gerilimlerinin birbirlerine göre ayarlanabilmesi için bir adet DC/DC gerilim dönüştürücü içerir.…”

Research on Control Strategy of Hybrid Energy Storage System in Distributed Generation

“…Research has proved that hybrid storage system can make full use of different storage medium, which prolongs the service time of the storage system [2];The use of high pass filter to attribute the power and taking the SOC(State Of Charge) of battery into consideration can prolong the service time of battery [3]; in [4], moving average filtering was used to distribute the power, and the time constant is adjusted base on the SOC of battery, which achieve the reasonable distribution of power between battery and super-capacitor. A control strategy that combines fuzzy control with low pass filtering was proposed in [5].…”