In this work, a hybrid power module comprising of a direct methanol fuel cell (DMFC) and a Li-ion battery has been proposed for low power applications. The challenges associated with low power and small DMFCs were investigated and the performance of commercial Li-ion batteries was evaluated. At low current demand (or low power), methanol leakage through the proton exchange membrane (PEM) reduces the efficiency of a DMFC. Consequently, a proton conducting methanol barrier layer made from phospho-silica glass(PSG) was developed. At optimized deposition conditions, the PSG layers had low methanol permeability and moderate conductivity. The accumulation of CO2 inside the fuel tank was addressed by fabricating CO2 vents. Poly (dimethyl siloxane) (PDMS) and poly (1-trimethyl silyl propyne) (PTMSP) base polymers were used as the backbone material for these vents. The selectivity of CO2 transport through the vent was further enhanced by using additives like 1, 6-divinylperfluorohexane. Finally, the effects of self-discharge and voltage loss were evaluated for Panasonic coin cells and thin film LiPON cells. It was observed that the thin film battery outperformed the others in terms of low energy loss. Nonetheless, the performance of small Panasonic coin cells with vanadium oxide cathode was comparable at low discharge rates of less than 0.01% depth of discharge. Lastly, it was also observed that the batteries have stable cycles at low discharge rates.

Syftet med arbetet var att undersöka hur ett nyproducerat batterihybridfartyg av PSV-typ (plattform supply vessel) bör operera för att uppnå en så energieffektiv drift som möjligt utan att äventyra säkerhet eller redundanskrav. Att framföra ett fartyg så energieffektivt som möjligt är något som är av hög prioritet till sjöss, dels ur ett ekonomiskt perspektiv men även ur miljösynpunkt, då sjöfartsbranschen ständigt arbetar för en minskad miljöpåverkan. Även nyproducerade fartyg, byggda med modern teknik som ger goda förutsättningar för en energieffektiv drift ställer stora krav på att det tydligt framgår hur fartyget ska framföras för att nyttja fartygets fulla potential och uppnå optimal drift. För att ta fram procedurer över hur fartygen bör operera har loggade och teoretiska data från fartyget Coey Viking sammanställts, och presenteras i samråd med Viking Supply Ships. Resultatet innefattar generatorkombinationers specifika bränsleförbrukning, lågtrycks-dual-fuel-motorers generella miljöpåverkan med avseende på metanslip och fartygets loggade effektförbrukning till kaj. Resultatet visade att hög generatorlast resulterade i optimal specifik bränsleförbrukningen, att låga generatorlaster genererade stort metanslip samt att en förändrad elkraftstyrning tillsammans med fartygets energilagring möjliggör en förbättrad drift till kaj med en minskad miljöpåverkan. Arbetet öppnar upp för vidare forskning inom optimal peak-shaving-effekt, hur energilagringens storlek påverkar driftsmöjligheter och hur peak-shaving till kaj på ett stabilt sätt reglertekniskt bör styras. / The purpose of this undertaking was to investigate a new built battery-hybrid-vessel of PSV-type (platform supply vessel) and its operational ability to achieve the most energy efficient operation without jeopardizing safety or redundancy. The energy efficient operation of a vessel is of great priority in the maritime industry, not only because of economical profit but also based on environmental perspective, since the maritime industry is constantly aiming towards a decreased environmental impact. Newly built vessels containing modern technology opens up great opportunity in achieving energy efficient operation, though it sets high standard regarding correct operation of the vessel to use its full potential and achieve optimal running. To be able to present procedures regarding the vessel’s operation, logged and theoretical data from the vessel Coey Viking has been compiled and is presented in consultation with Viking Supply Ships. The results refered to different generator combination’s specific fuel consumption, the general environmental impact of low pressure dual fuel engines with respect to methane slip and the vessel’s logged power consumption in port.  The result indicated that a high generator load resulted in optimal specific fuel consumption, while low generator loads resulted in poor specific fuel consumption together with an increase in methane slip. The result also showed that the vessel’s energy storage together with a change in the PMS-system (Power Management System) would enable an improved power supply in port with shore connection. The paper raises questions to be answered in further research regarding optimal peak-shaving effect, what impact the size of the energy storage would have on operational capability and how peak shaving in port with shore connection appropriately should be regulated.

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This thesis deals with the problematic of lead acid batteries for HEVs. It starts with classification of electrochemical cells then proceeds to focus on lead acid batteries, mainly because they are the most used source of electrical power in automotive industry. The practical part of the work describes the process of manufacturing the electrode system used in the later parts. The experimental part is focused on the behaviour of the cells under conditions that appear in hybrid electric vehicles. The effect of aditives in active matter of the negative electrode on the parameters of the cells is observed, such as voltage, capacity and operating life