(Ⅰ)设椭圆的右焦点为F2(c,0),
由|AB|=
|F1F2|,可得
3
2
=
a2+b2
×2c,化为a2+b2=3c2.
3
2
又b2=a2-c2,∴a2=2c2.
∴e=
=c a
.
2
2
(Ⅱ)由(Ⅰ)可得b2=c2.因此椭圆方程为
+x2 2c2
=1.y2 c2
设P(x0,y0),由F1(-c,0),B(0,c),可得
=(x0+c,y0),
F1P
=(c,c).
F1B
∵