A 27-year-old woman convicted of manslaughter in the 1985 death of her husband despite her claim it was the only way she could escape his battering was sentenced Friday to 15 to 20 years at the state prison for women in Framingham.

Lisa Becker-Grimshaw was ordered to begin the prison term in 10 days and will be given credit for three years already served in jail while awaiting trial in the beating death of her husband, Thomas Grimshaw, who was 30 at the time.Two others have admitted they beat Thomas Grimshaw to death with baseball bats at a boat ramp in Chicopee on June 5, 1985, while Becker-Grimshaw sat nearby in a parked car. The two others, one a juvenile at the time, were both sentenced to prison terms.