def METHOD_NAME(self):
    vpair = self.ie_LTO[0]
    assert vpair.voltage == approx(2.78583901)
    assert vpair.mAh == approx(13400.7411749)
    assert vpair.mass_charge == approx(79.8658)
    assert vpair.mass_discharge == approx(83.3363)
    assert vpair.vol_charge == approx(37.553684467)
    assert vpair.vol_discharge == approx(37.917719932)
    assert vpair.frac_charge == approx(0)
    assert vpair.frac_discharge == approx(0.14285714285714285)
    assert vpair.x_charge == approx(0)
    assert vpair.x_discharge == approx(0.5)
    # reconstruct the voltage pair
    dct = vpair.as_dict()
    vv = InsertionVoltagePair.from_dict(dct)
    assert vv.entry_charge.energy == approx(-105.53608265)
    assert vv.voltage == approx(2.78583901)