diff --git a/erpnext/stock/doctype/serial_no/serial_no.py b/erpnext/stock/doctype/serial_no/serial_no.py
index 884cb1e..244f3e2 100644
--- a/erpnext/stock/doctype/serial_no/serial_no.py
+++ b/erpnext/stock/doctype/serial_no/serial_no.py
@@ -7,7 +7,16 @@
 import frappe
 from frappe import ValidationError, _
 from frappe.model.naming import make_autoname
-from frappe.utils import add_days, cint, cstr, flt, get_link_to_form, getdate, nowdate
+from frappe.utils import (
+	add_days,
+	cint,
+	cstr,
+	flt,
+	get_link_to_form,
+	getdate,
+	nowdate,
+	safe_json_loads,
+)
 
 from erpnext.controllers.stock_controller import StockController
 from erpnext.stock.get_item_details import get_reserved_qty_for_so
@@ -566,7 +575,8 @@
 @frappe.whitelist()
 def auto_fetch_serial_number(qty, item_code, warehouse,
 		posting_date=None, batch_nos=None, for_doctype=None, exclude_sr_nos=None):
-	filters = { "item_code": item_code, "warehouse": warehouse }
+
+	filters = frappe._dict({"item_code": item_code, "warehouse": warehouse})
 
 	if exclude_sr_nos is None:
 		exclude_sr_nos = []
@@ -574,13 +584,14 @@
 		exclude_sr_nos = get_serial_nos(clean_serial_no_string("\n".join(exclude_sr_nos)))
 
 	if batch_nos:
-		try:
-			filters["batch_no"] = json.loads(batch_nos) if (type(json.loads(batch_nos)) == list) else [json.loads(batch_nos)]
-		except Exception:
-			filters["batch_no"] = [batch_nos]
+		batch_nos = safe_json_loads(batch_nos)
+		if isinstance(batch_nos, list):
+			filters.batch_no = batch_nos
+		elif isinstance(batch_nos, str):
+			filters.batch_no = [batch_nos]
 
 	if posting_date:
-		filters["expiry_date"] = posting_date
+		filters.expiry_date = posting_date
 
 	serial_numbers = []
 	if for_doctype == 'POS Invoice':