diff --git a/CHANGELOG.md b/CHANGELOG.md
index 3a112635..d5c36a31 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,12 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](http://keepachangelog.com/)
 and this project adheres to [Semantic Versioning](http://semver.org/).
 
+## [Unreleased]
+
+### Fixed
+
+- Ranges across Z and AA columns incorrectly threw an exception - [#545](https://github.com/PHPOffice/PhpSpreadsheet/issues/545)
+
 ## [1.3.0] - 2018-06-10
 
 ### Added
diff --git a/src/PhpSpreadsheet/Cell/Coordinate.php b/src/PhpSpreadsheet/Cell/Coordinate.php
index 077e8d06..366ec492 100644
--- a/src/PhpSpreadsheet/Cell/Coordinate.php
+++ b/src/PhpSpreadsheet/Cell/Coordinate.php
@@ -340,7 +340,7 @@ abstract class Coordinate
         // Explode spaces
         $cellBlocks = self::getCellBlocksFromRangeString($pRange);
         foreach ($cellBlocks as $cellBlock) {
-            $returnValue = array_merge($returnValue, static::getReferencesForCellBlock($cellBlock));
+            $returnValue = array_merge($returnValue, self::getReferencesForCellBlock($cellBlock));
         }
 
         //    Sort the result by column and row
@@ -360,8 +360,6 @@ abstract class Coordinate
      *
      * @param string $cellBlock A cell range e.g. A4:B5
      *
-     * @throws Exception
-     *
      * @return array All individual cells in that range
      */
     private static function getReferencesForCellBlock($cellBlock)
@@ -385,23 +383,25 @@ abstract class Coordinate
 
             // Range...
             list($rangeStart, $rangeEnd) = $range;
-            list($startCol, $startRow) = static::extractColumnAndRow($rangeStart);
-            list($endCol, $endRow) = static::extractColumnAndRow($rangeEnd);
-            ++$endCol;
+            list($startColumn, $startRow) = self::coordinateFromString($rangeStart);
+            list($endColumn, $endRow) = self::coordinateFromString($rangeEnd);
+            $startColumnIndex = self::columnIndexFromString($startColumn);
+            $endColumnIndex = self::columnIndexFromString($endColumn);
+            ++$endColumnIndex;
 
             // Current data
-            $currentCol = $startCol;
+            $currentColumnIndex = $startColumnIndex;
             $currentRow = $startRow;
 
-            static::validateRange($cellBlock, $startCol, $endCol, $currentRow, $endRow);
+            self::validateRange($cellBlock, $startColumnIndex, $endColumnIndex, $currentRow, $endRow);
 
             // Loop cells
-            while ($currentCol < $endCol) {
+            while ($currentColumnIndex < $endColumnIndex) {
                 while ($currentRow <= $endRow) {
-                    $returnValue[] = $currentCol . $currentRow;
+                    $returnValue[] = self::stringFromColumnIndex($currentColumnIndex) . $currentRow;
                     ++$currentRow;
                 }
-                ++$currentCol;
+                ++$currentColumnIndex;
                 $currentRow = $startRow;
             }
         }
@@ -409,18 +409,6 @@ abstract class Coordinate
         return $returnValue;
     }
 
-    /**
-     * Extract the column and row from a cell reference in the format [$column, $row].
-     *
-     * @param string $cell
-     *
-     * @return array
-     */
-    private static function extractColumnAndRow($cell)
-    {
-        return sscanf($cell, '%[A-Z]%d');
-    }
-
     /**
      * Convert an associative array of single cell coordinates to values to an associative array
      * of cell ranges to values.  Only adjacent cell coordinates with the same
@@ -524,16 +512,14 @@ abstract class Coordinate
      * row.
      *
      * @param string $cellBlock The original range, for displaying a meaningful error message
-     * @param string $startCol
-     * @param string $endCol
+     * @param int $startColumnIndex
+     * @param int $endColumnIndex
      * @param int $currentRow
      * @param int $endRow
-     *
-     * @throws Exception
      */
-    private static function validateRange($cellBlock, $startCol, $endCol, $currentRow, $endRow)
+    private static function validateRange($cellBlock, $startColumnIndex, $endColumnIndex, $currentRow, $endRow)
     {
-        if ($startCol >= $endCol || $currentRow > $endRow) {
+        if ($startColumnIndex >= $endColumnIndex || $currentRow > $endRow) {
             throw new Exception('Invalid range: "' . $cellBlock . '"');
         }
     }
diff --git a/tests/data/CellExtractAllCellReferencesInRange.php b/tests/data/CellExtractAllCellReferencesInRange.php
index 678fe512..cf093289 100644
--- a/tests/data/CellExtractAllCellReferencesInRange.php
+++ b/tests/data/CellExtractAllCellReferencesInRange.php
@@ -140,4 +140,13 @@ return [
         ],
         'B4:B6 B8',
     ],
+    [
+        [
+            'Z2',
+            'Z3',
+            'AA2',
+            'AA3',
+        ],
+        'Z2:AA3',
+    ],
 ];