diff --git a/libraries/AP_BattMonitor/AP_BattMonitor_SMBus.cpp b/libraries/AP_BattMonitor/AP_BattMonitor_SMBus.cpp
index ffaae0b9f1..1eb3919cf6 100644
--- a/libraries/AP_BattMonitor/AP_BattMonitor_SMBus.cpp
+++ b/libraries/AP_BattMonitor/AP_BattMonitor_SMBus.cpp
@@ -173,6 +173,45 @@ bool AP_BattMonitor_SMBus::read_word(uint8_t reg, uint16_t& data) const
     return true;
 }
 
+// read_block - returns number of characters read if successful, zero if unsuccessful
+uint8_t AP_BattMonitor_SMBus::read_block(uint8_t reg, uint8_t* data, uint8_t len) const
+{
+    // get length
+    uint8_t bufflen;
+    // read byte (first byte indicates the number of bytes in the block)
+    if (!_dev->read_registers(reg, &bufflen, 1)) {
+        return 0;
+    }
+
+    // sanity check length returned by smbus
+    if (bufflen == 0 || bufflen > len) {
+        return 0;
+    }
+
+    // buffer to hold results (2 extra byte returned holding length and PEC)
+    const uint8_t read_size = bufflen + 1 + (_pec_supported ? 1 : 0);
+    uint8_t buff[read_size];
+
+    // read bytes
+    if (!_dev->read_registers(reg, buff, read_size)) {
+        return 0;
+    }
+
+    // check PEC
+    if (_pec_supported) {
+        const uint8_t pec = get_PEC(_address, reg, true, buff, bufflen+1);
+        if (pec != buff[bufflen+1]) {
+            return 0;
+        }
+    }
+
+    // copy data (excluding length & PEC)
+    memcpy(data, &buff[1], bufflen);
+
+    // return success
+    return bufflen;
+}
+
 /// get_PEC - calculate packet error correction code of buffer
 uint8_t AP_BattMonitor_SMBus::get_PEC(const uint8_t i2c_addr, uint8_t cmd, bool reading, const uint8_t buff[], uint8_t len) const
 {
diff --git a/libraries/AP_BattMonitor/AP_BattMonitor_SMBus.h b/libraries/AP_BattMonitor/AP_BattMonitor_SMBus.h
index 3c26aba47e..7b5330f91a 100644
--- a/libraries/AP_BattMonitor/AP_BattMonitor_SMBus.h
+++ b/libraries/AP_BattMonitor/AP_BattMonitor_SMBus.h
@@ -10,7 +10,8 @@
 #define AP_BATTMONITOR_SMBUS_BUS_INTERNAL           0
 #define AP_BATTMONITOR_SMBUS_BUS_EXTERNAL           1
 #define AP_BATTMONITOR_SMBUS_I2C_ADDR               0x0B
-#define AP_BATTMONITOR_SMBUS_TIMEOUT_MICROS         5000000 // sensor becomes unhealthy if no successful readings for 5 seconds
+#define AP_BATTMONITOR_SMBUS_TIMEOUT_MICROS         5000000         // sensor becomes unhealthy if no successful readings for 5 seconds
+#define AP_BATTMONITOR_SMBUS_READ_BLOCK_MAXIMUM_TRANSFER 0x20       // A Block Read or Write is allowed to transfer a maximum of 32 data bytes.
 
 class AP_BattMonitor_SMBus : public AP_BattMonitor_Backend
 {
@@ -84,6 +85,9 @@ protected:
      // returns true if read was successful, false if failed
     bool read_word(uint8_t reg, uint16_t& data) const;
 
+    // read_block - returns number of characters read if successful, zero if unsuccessful
+    uint8_t read_block(uint8_t reg, uint8_t* data, uint8_t len) const;
+
     // get_PEC - calculate PEC for a read or write from the battery
     // buff is the data that was read or will be written
     uint8_t get_PEC(const uint8_t i2c_addr, uint8_t cmd, bool reading, const uint8_t buff[], uint8_t len) const;
diff --git a/libraries/AP_BattMonitor/AP_BattMonitor_SMBus_Generic.cpp b/libraries/AP_BattMonitor/AP_BattMonitor_SMBus_Generic.cpp
index 83d33c8984..9d02f30888 100644
--- a/libraries/AP_BattMonitor/AP_BattMonitor_SMBus_Generic.cpp
+++ b/libraries/AP_BattMonitor/AP_BattMonitor_SMBus_Generic.cpp
@@ -3,7 +3,6 @@
 #include <AP_Math/AP_Math.h>
 #include "AP_BattMonitor.h"
 #include "AP_BattMonitor_SMBus_Generic.h"
-#include <utility>
 
 uint8_t smbus_cell_ids[] = { 0x3f,  // cell 1
                              0x3e,  // cell 2
@@ -23,7 +22,6 @@ uint8_t smbus_cell_ids[] = { 0x3f,  // cell 1
 #endif
 };
 
-#define SMBUS_READ_BLOCK_MAXIMUM_TRANSFER    0x20   // A Block Read or Write is allowed to transfer a maximum of 32 data bytes.
 #define SMBUS_CELL_COUNT_CHECK_TIMEOUT       15     // check cell count for up to 15 seconds
 
 /*
@@ -129,45 +127,6 @@ void AP_BattMonitor_SMBus_Generic::timer()
     read_cycle_count();
 }
 
-// read_block - returns number of characters read if successful, zero if unsuccessful
-uint8_t AP_BattMonitor_SMBus_Generic::read_block(uint8_t reg, uint8_t* data) const
-{
-    // get length
-    uint8_t bufflen;
-    // read byte (first byte indicates the number of bytes in the block)
-    if (!_dev->read_registers(reg, &bufflen, 1)) {
-        return 0;
-    }
-
-    // sanity check length returned by smbus
-    if (bufflen == 0 || bufflen > SMBUS_READ_BLOCK_MAXIMUM_TRANSFER) {
-        return 0;
-    }
-
-    // buffer to hold results (2 extra byte returned holding length and PEC)
-    const uint8_t read_size = bufflen + 1 + (_pec_supported ? 1 : 0);
-    uint8_t buff[read_size];
-
-    // read bytes
-    if (!_dev->read_registers(reg, buff, read_size)) {
-        return 0;
-    }
-
-    // check PEC
-    if (_pec_supported) {
-        uint8_t pec = get_PEC(AP_BATTMONITOR_SMBUS_I2C_ADDR, reg, true, buff, bufflen+1);
-        if (pec != buff[bufflen+1]) {
-            return 0;
-        }
-    }
-
-    // copy data (excluding PEC)
-    memcpy(data, &buff[1], bufflen);
-
-    // return success
-    return bufflen;
-}
-
 // check if PEC supported with the version value in SpecificationInfo() function
 // returns true once PEC is confirmed as working or not working
 bool AP_BattMonitor_SMBus_Generic::check_pec_support()
@@ -194,8 +153,8 @@ bool AP_BattMonitor_SMBus_Generic::check_pec_support()
     }
 
     // check manufacturer name
-    uint8_t buff[SMBUS_READ_BLOCK_MAXIMUM_TRANSFER + 1] {};
-    if (read_block(BATTMONITOR_SMBUS_MANUFACTURE_NAME, buff)) {
+    uint8_t buff[AP_BATTMONITOR_SMBUS_READ_BLOCK_MAXIMUM_TRANSFER + 1] {};
+    if (read_block(BATTMONITOR_SMBUS_MANUFACTURE_NAME, buff, sizeof(buff))) {
         // Hitachi maxell batteries do not support PEC
         if (strcmp((char*)buff, "Hitachi maxell") == 0) {
             _pec_supported = false;
@@ -209,4 +168,3 @@ bool AP_BattMonitor_SMBus_Generic::check_pec_support()
 	_pec_confirmed = true;
 	return true;
 }
-
diff --git a/libraries/AP_BattMonitor/AP_BattMonitor_SMBus_Generic.h b/libraries/AP_BattMonitor/AP_BattMonitor_SMBus_Generic.h
index fd19a830b2..7edc4a6264 100644
--- a/libraries/AP_BattMonitor/AP_BattMonitor_SMBus_Generic.h
+++ b/libraries/AP_BattMonitor/AP_BattMonitor_SMBus_Generic.h
@@ -25,9 +25,6 @@ private:
     // returns true once PEC is confirmed as working or not working
     bool check_pec_support();
 
-    // read_block - returns number of characters read if successful, zero if unsuccessful
-    uint8_t read_block(uint8_t reg, uint8_t* data) const;
-
     uint8_t _pec_confirmed; // count of the number of times PEC has been confirmed as working
     uint32_t _last_cell_update_us[BATTMONITOR_SMBUS_NUM_CELLS_MAX]; // system time of last successful read of cell voltage
     uint32_t _cell_count_check_start_us;  // system time we started attempting to count the number of cells
diff --git a/libraries/AP_BattMonitor/AP_BattMonitor_SMBus_SUI.cpp b/libraries/AP_BattMonitor/AP_BattMonitor_SMBus_SUI.cpp
index b1382f7d9e..7d8aacce33 100644
--- a/libraries/AP_BattMonitor/AP_BattMonitor_SMBus_SUI.cpp
+++ b/libraries/AP_BattMonitor/AP_BattMonitor_SMBus_SUI.cpp
@@ -65,38 +65,6 @@ void AP_BattMonitor_SMBus_SUI::timer()
     update_health();
 }
 
-// read_block - returns true if successful
-bool AP_BattMonitor_SMBus_SUI::read_block(uint8_t reg, uint8_t* data, uint8_t len) const
-{
-    // buffer to hold results (2 extra byte returned holding length and PEC)
-    uint8_t buff[len+2];
-
-    // read bytes
-    if (!_dev->read_registers(reg, buff, sizeof(buff))) {
-        return false;
-    }
-
-    // get length
-    uint8_t bufflen = buff[0];
-
-    // sanity check length returned by smbus
-    if (bufflen == 0 || bufflen > len) {
-        return false;
-    }
-
-    // check PEC
-    uint8_t pec = get_PEC(_address, reg, true, buff, bufflen+1);
-    if (pec != buff[bufflen+1]) {
-        return false;
-    }
-
-    // copy data (excluding PEC)
-    memcpy(data, &buff[1], bufflen);
-
-    // return success
-    return true;
-}
-
 // read_bare_block - returns true if successful
 bool AP_BattMonitor_SMBus_SUI::read_block_bare(uint8_t reg, uint8_t* data, uint8_t len) const
 {
@@ -129,7 +97,7 @@ void AP_BattMonitor_SMBus_SUI::read_cell_voltages()
         // we can't read voltage of all cells. get overall pack voltage to work out
         // an average for remaining cells
         uint16_t total_mv;
-        if (read_block(BATTMONITOR_SMBUS_VOLTAGE, (uint8_t *)&total_mv, sizeof(total_mv))) {
+        if (read_word(BATTMONITOR_SMBUS_VOLTAGE, total_mv)) {
             // if total voltage is below pack_voltage_mv then we will
             // read zero volts for the extra cells.
             total_mv = MAX(total_mv, pack_voltage_mv);
diff --git a/libraries/AP_BattMonitor/AP_BattMonitor_SMBus_SUI.h b/libraries/AP_BattMonitor/AP_BattMonitor_SMBus_SUI.h
index 5ba8ad913e..506f5bc541 100644
--- a/libraries/AP_BattMonitor/AP_BattMonitor_SMBus_SUI.h
+++ b/libraries/AP_BattMonitor/AP_BattMonitor_SMBus_SUI.h
@@ -21,8 +21,7 @@ private:
     void read_cell_voltages();
     void update_health();
 
-    // read_block - returns number of characters read if successful, zero if unsuccessful
-    bool read_block(uint8_t reg, uint8_t* data, uint8_t len) const;
+    // read_block_bare - returns number of characters read if successful, zero if unsuccessful
     bool read_block_bare(uint8_t reg, uint8_t* data, uint8_t len) const;
 
     const uint8_t cell_count;
diff --git a/libraries/AP_BattMonitor/AP_BattMonitor_SMBus_Solo.cpp b/libraries/AP_BattMonitor/AP_BattMonitor_SMBus_Solo.cpp
index 0528d70ca6..5d4be88342 100644
--- a/libraries/AP_BattMonitor/AP_BattMonitor_SMBus_Solo.cpp
+++ b/libraries/AP_BattMonitor/AP_BattMonitor_SMBus_Solo.cpp
@@ -95,34 +95,3 @@ void AP_BattMonitor_SMBus_Solo::timer()
 
     read_cycle_count();
 }
-
-// read_block - returns number of characters read if successful, zero if unsuccessful
-uint8_t AP_BattMonitor_SMBus_Solo::read_block(uint8_t reg, uint8_t* data, uint8_t max_len) const
-{
-    uint8_t buff[max_len+2];    // buffer to hold results (2 extra byte returned holding length and PEC)
-
-    // read bytes
-    if (!_dev->read_registers(reg, buff, sizeof(buff))) {
-        return 0;
-    }
-
-    // get length
-    uint8_t bufflen = buff[0];
-
-    // sanity check length returned by smbus
-    if (bufflen == 0 || bufflen > max_len) {
-        return 0;
-    }
-
-    // check PEC
-    uint8_t pec = get_PEC(_address, reg, true, buff, bufflen+1);
-    if (pec != buff[bufflen+1]) {
-        return 0;
-    }
-
-    // copy data (excluding PEC)
-    memcpy(data, &buff[1], bufflen);
-
-    // return success
-    return bufflen;
-}
diff --git a/libraries/AP_BattMonitor/AP_BattMonitor_SMBus_Solo.h b/libraries/AP_BattMonitor/AP_BattMonitor_SMBus_Solo.h
index d343f3f7bd..2200220b46 100644
--- a/libraries/AP_BattMonitor/AP_BattMonitor_SMBus_Solo.h
+++ b/libraries/AP_BattMonitor/AP_BattMonitor_SMBus_Solo.h
@@ -15,8 +15,5 @@ private:
 
     void timer(void) override;
 
-    // read_block - returns number of characters read if successful, zero if unsuccessful
-    uint8_t read_block(uint8_t reg, uint8_t* data, uint8_t max_len) const;
-
     uint8_t _button_press_count;
 };