diff --git a/gufe/solventcomponent.py b/gufe/solventcomponent.py
index 3736e0a5..a6d20b12 100644
--- a/gufe/solventcomponent.py
+++ b/gufe/solventcomponent.py
@@ -61,13 +61,13 @@ def __init__(self, *,  # force kwarg usage
             norm = positive_ion.strip('-+').capitalize()
             if norm not in _CATIONS:
                 raise ValueError(f"Invalid positive ion, got {positive_ion}")
-            positive_ion = norm
+            positive_ion = norm + '+'
         self._positive_ion = positive_ion
         if negative_ion is not None:
             norm = negative_ion.strip('-+').capitalize()
             if norm not in _ANIONS:
                 raise ValueError(f"Invalid negative ion, got {negative_ion}")
-            negative_ion = norm
+            negative_ion = norm + '-'
         self._negative_ion = negative_ion
 
         self._neutralize = neutralize
diff --git a/gufe/tests/test_solvents.py b/gufe/tests/test_solvents.py
index a62975fb..81947d93 100644
--- a/gufe/tests/test_solvents.py
+++ b/gufe/tests/test_solvents.py
@@ -23,7 +23,8 @@ def test_hash(pos, neg):
 
     assert s1 == s2
     assert hash(s1) == hash(s2)
-
+    assert s2.positive_ion == 'Na+'
+    assert s2.negative_ion == 'Cl-'
 
 def test_neq():
     s1 = SolventComponent(positive_ion='Na', negative_ion='Cl')
@@ -36,8 +37,8 @@ def test_to_dict():
     s = SolventComponent(positive_ion='Na', negative_ion='Cl')
 
     assert s.to_dict() == {'smiles': 'O',
-                           'positive_ion': 'Na',
-                           'negative_ion': 'Cl',
+                           'positive_ion': 'Na+',
+                           'negative_ion': 'Cl-',
                            'neutralize': True,
                            'ion_concentration': None}