We have employed a nonlinear polarization rotation technique to realize the self-starting passive mode-locking in an erbium-doped fiber laser with positive dispersion. The laser can emit high-energy dissipative solitons without wave-breaking. The pulse-shaping mechanism, which is qualitatively distinct from the conservative solitons in negative dispersion cavity, may originate from the laser gain, loss, NPR, cavity dispersion, or other fiber nonlinearity effects. To our best knowledge, it is the first report on the experimental observations for high-energy wave-breaking-free dissipative solitons forming in a fiber laser with ultra-large net-normal cavity dispersion. The spectrum of these strongly chirped pulses covers the wavelength range from 1530 to 1660 nm. The FWHM width of the spectrum can be as large as 42 nm, and the maximal total energy of a single-pulse is estimated to be ~34.4 nJ.