Old PSP aka PSP1000 use 1800maH battery and for New PSP2000 aka PSP Slim use 1200maH battery...you can calculate now asa masdugay mahurot ang power...we can use our old PSP battery for PSP Slim and extend playing time up 10hrs +/- naa may optional cover nga iilis sa battery pack sa SLim PSP para magamit nato ang 1800maH na battery...yet wala pay available sa local market..we just need to wait...