Best Memory Saver For Car Battery: Compare 10 Options

#1 · Best Overall

1. EZRED MS4000

• Weight: 1.9 lb

Best for: Self-contained battery-swap power.

Why it ranks #1: Includes a 12-volt, 4.5 amp-hour sealed lead-acid battery, a built-in charger, direct-wired OBDII connector, and connection and low-battery LEDs.

A built-in 12-volt, 4.5 amp-hour sealed lead-acid battery lets the EZRED MS4000 supply backup power without requiring a separate battery at the work area. Its direct-wired OBDII connector maintains vehicle settings and drive-ability codes during starter-battery changes, including radio, clock, and keyless-entry information.

The internal battery and direct-wired OBDII connector make this a compact, integrated option for battery service: connect it to the vehicle port and the unit supplies power to preserve settings and codes. A green LED indicates connection, while the amber LED signals that internal voltage is at 11.6 volts or lower and charging is due soon. The built-in charger supports maintaining the included battery for future use, and a power switch controls operation.

Skip it if you need a cable powered by a separate 12V source; the VSTM VST-939 offers a 10-foot cable for that workflow.

For a battery changer who wants an integrated backup source, the MS4000 combines its own sealed lead-acid battery with an OBDII connection. Account for recharging the internal battery when its amber low-voltage indicator appears.

Listed on Amazon as: EZRED MS4000 Automotive Memory Saver With Built In Charger , Black

#2 · Longest Cable

2. VSTM OBD II Cable

• Weight: 10.6 oz

Best for: Long-reach cable for battery swaps.

Why it ranks #2: Its 10-foot cable offers more reach than the stated 3-to-5-foot mainstream cables, and it accepts power through a 12-volt source.

A 10-foot cable gives the VSTM VST-939 extra working reach during a battery swap, allowing more flexibility in where the backup power source sits. Gold-plated OBD pins are specified for improved contact and anti-oxidation, while the cable links a 12-volt DC source with the vehicle to preserve codes and electronic presets.

The three-meter cable can make battery service easier when the available 12V source cannot sit close to the vehicle’s OBDII port. VSTM also says the cable can connect to another working car through its cigarette-lighter plug when a jump starter or lead-acid battery is unavailable. Gold-plated pins support stable electrical transmission, and the listed dual-safety system includes reverse-polarity protection to help guard against incorrect connections.

Skip it if you need an included backup battery; the EZRED MS4000 contains a 12V, 4.5Ah sealed lead-acid battery.

The VSTM VST-939 suits technicians who need extra cable reach and already have a 12V source or access to another working car. Its external-power setup is the key boundary: it does not provide a self-contained backup battery.

Listed on Amazon as: VSTM OBD II ECU Memory Saver Cable,12V Emergency Power for Car Battery Swap

#3 · Leakage Detection

3. AUTOOL BT30

Best for: Memory saving and fuse diagnostics.

Why it ranks #3: Displays voltage and current from a 12-volt DC source and adds fuse-by-fuse leakage detection, beyond its OBDII memory-saver function.

The AUTOOL BT30 pairs an OBDII memory-saver cable with voltage and current readings and a fuse-leakage detection function, extending its role beyond battery replacement. It works with a 12V DC power source, and its red voltage and blue current display gives users a way to observe the supply while servicing the vehicle.

During a battery change, the BT30 connects a spare battery to the vehicle OBD port and displays voltage and current, helping users monitor the power connection. Its stated compatibility with 12V DC sources includes a running starter, a 12V lead-acid battery, or another automotive 12V outlet. For troubleshooting, the leakage-detection workflow uses the display while fuses are removed one by one, so the same kit can support memory retention and fuse investigation.

Skip it if you want USB power-bank operation with LED and speaker cues; the JEUCLEL JEUS158 uses that power and status approach.

The BT30 suits a technician who wants memory support plus voltage, current, and fuse-leakage checks from a 12V source. Its broader diagnostic workflow is useful only if you can provide that external power supply.

Listed on Amazon as: AUTOOL OBD II Car Memory Saver Cable 12V Vehicle ECU Emergency Power Supply Cable Digital Display OBD II Battery Leakage Detective Kit with 3A Fuse & 2 Alligator Clips

#4 · Battery Clamp Power

4. Autel MaxiBAS BTMS

• Weight: 100 g

Best for: Autel 12V backup-battery connection.

Why it ranks #4: Its included battery clamp connects to a 12-volt backup battery, and the product is listed for all 12-volt vehicles.

Autel’s MaxiBAS BTMS uses a dedicated battery clamp to connect a 12V backup battery, giving battery-replacement work a direct backup-power path. It is described as retaining vehicle codes and electronic presets when onboard-computer power is interrupted, making it a professional-oriented option for preserving vehicle data during battery service.

The battery clamp and 12V backup-battery connection let the user maintain power while the vehicle battery is being replaced, rather than relying on the disconnected battery. Autel identifies the unit as a memory saver for all 12V vehicles and says it retains codes and electronic presets. The supplied information names MaxiBAS BTMS and accessories as included components, but does not detail cable length or monitoring indicators, so those should not be assumed for a particular workflow.

Skip it if you need listed real-time voltage and current readings; the MR CARTOOL B80 specifies both on its display.

Autel’s MaxiBAS BTMS is suited to a professional or frequent battery-service user with a 12V backup battery and a need to preserve codes and presets. Consider the unspecified cable and display details if those affect your work setup.

Listed on Amazon as: 2026 Autel MaxiBAS BTMS OBD2 Memory Saver, for All 12V Vehicles

#5 · Live Display

5. MR CARTOOL B80

• Weight: 0.28 kg

Best for: Live voltage and current monitoring.

Why it ranks #5: The OBD2 cable provides real-time voltage and current display, with a listed minimum operating voltage of 10 volts and a 24-month warranty.

A real-time voltage and current display lets the MR CARTOOL B80 show power readings during battery replacement, adding visibility to its OBD2 memory-saver cable workflow. It connects a spare battery to the vehicle’s OBD2 interface to help prevent loss of operating data, and its specified minimum operating voltage is 10 volts.

The display’s voltage and current readings give the user information about the backup supply while the B80 connects it to the vehicle’s OBD2 port. This can help monitor the power arrangement during a battery change rather than treating the cable as an unobserved link. The stated 10-volt minimum operating voltage is a practical limit for selecting a compatible supply; the supplied facts identify a cable, not an included battery.

Skip it if you need a self-contained backup battery; the EZRED MS4000 includes its own 12V sealed lead-acid battery.

The B80 suits battery-service users who want to see voltage and current while a spare battery powers the vehicle through OBD2. Its 10-volt minimum and separate-source workflow matter when choosing a compatible backup supply.

Listed on Amazon as: MR CARTOOL OBD2 Car Memory Saver Cable with Voltage/Current Display

#6

6. JEUCLEL JEUS158

• Weight: 0.13 kg

Best for: USB power bank connection.

Why it ranks #6: Runs from a USB power bank and uses three status LEDs plus a speaker, offering a distinct power-source option for battery replacement.

USB power lets the JEUCLEL memory saver draw from a power bank, offering a portable power-source option for protecting vehicle settings during a battery change. Three LED indicators and a speaker communicate device status, while the listed memory protection covers dashboard information, clock, stereo, memory seats, and ABS information.

Connecting to a USB power bank can make the JEUS158 convenient for buyers who already carry one, without relying on the vehicle battery during replacement. Its three LEDs and speaker provide status cues, helping users follow the device’s operation as it powers the OBDII memory-saving process. The product information names several settings and systems it protects, including stereo and memory seats; it does not specify the power bank capacity required.

Skip it if you want a supplied internal backup battery; the EZRED MS4000 includes a sealed lead-acid battery.

The JEUS158 fits a user who prefers USB power and wants LED and audible status cues while protecting vehicle memory. Keep a suitable power bank available, since the listed setup draws power externally rather than supplying its own battery.

Listed on Amazon as: USB Powered Vehicle OBD II Connector Memory Saver with Buzzer

#7

7. Clore SOLAR ESA30

• Weight: 5.6 oz

Best for: Simple 12V OBDII connector.

Why it ranks #7: Connects to the OBDII port and accepts any 12-volt power supply, such as a portable jump starter, but the listing describes a connector only.

The Clore Automotive SOLAR ESA30 connects to a vehicle’s OBD II port and uses a 12-volt power supply, such as a portable jump starter, to preserve memory during battery disconnection. Its straightforward connector role makes it a simple option for buyers who already have a compatible backup source.

Using a portable jump starter or another 12V supply as the source keeps the ESA30’s workflow centered on a familiar OBD II connection. The product information says the vehicle’s electrical system receives power through that connection during battery disconnection, supporting memory retention while the battery is changed. The supplied details describe a connector rather than an integrated power unit, so the user must bring the 12V source and manage that setup separately.

Skip it if you want an included internal battery; the EZRED MS4000 has a built-in 12V sealed lead-acid battery.

The ESA30 fits a battery-service user who already has a portable jump starter or other 12V supply and wants a simple OBD II connector. It is not a self-contained option, so the backup source must be part of your setup.

Listed on Amazon as: Clore Automotive SOLAR ESA30 OBD II Memory Saver Connector

#8

8. allsun GK504

• Weight: 2.39 oz

Best for: Cigarette-lighter memory keeper.

Why it ranks #8: Its cigarette-lighter connection offers a different setup, but it requires a separate 9-volt alkaline battery, which is not included.

The allsun GK504 connects through a vehicle cigarette lighter, offering a familiar plug-in approach to keeping onboard computer memory during battery replacement. Its rugged hard-plastic body and cable are specified for durability, while the 9-volt alkaline battery requirement gives buyers a clear power detail to account for before starting service.

Plugging into the cigarette lighter avoids using an OBDII connector as the listed vehicle-side connection, which can suit buyers whose preferred workflow uses that outlet. The GK504 is described as preserving radio presets, clock settings, seat memory, and anti-theft codes when disconnecting the battery. Its rugged hard-plastic body and durable cable suit repeated handling, but operation requires a 9-volt alkaline battery that is not included.

Skip it if you prefer an OBDII 16-pin plug-and-play connection; the YUANTUO 9V saver is specified for that port.

The GK504 fits owners or technicians who want a cigarette-lighter-connected memory keeper with a rugged body and cable. Plan ahead for its separate 9-volt alkaline battery, and choose another connection style if the lighter outlet is not your workflow.

Listed on Amazon as: All-Sun GK504 Automotive Setting Keeper Auto Vehicle Computer Memory Saver, 1 Pack

#9

9. YUANTUO 9V Saver

• Weight: 1.76 oz

Best for: OBDII 16-pin battery service.

Why it ranks #9: Lists compatibility with vehicles having an OBDII 16-pin interface and uses 9-volt input, but provides few further power-source details.

Compatibility with vehicles using an OBDII 16-pin interface is the YUANTUO memory saver’s defining fit, enabling a plug-and-play connection while the vehicle battery is disconnected. It runs on a 9-volt input and is described as retaining vehicle settings and memory to avoid reprogramming or resetting systems after replacement.

The 16-pin OBDII connection and simple plug-and-play setup make this unit a direct option for buyers servicing a vehicle with that interface. Its 9-volt input powers the memory-retention function while the main battery is disconnected, helping preserve critical settings and data through replacement or maintenance. At 1.76 ounces, it is also a lightweight item to keep with battery-service supplies; the supplied facts do not describe a status display or included backup battery.

Skip it if you want an integrated backup battery and charging indicators; the EZRED MS4000 includes a sealed lead-acid battery and LEDs.

This YUANTUO unit suits a buyer whose vehicle has an OBDII 16-pin port and who wants a lightweight, 9-volt memory saver for battery maintenance. Its listed compatibility is specific to that interface, so check the vehicle connection before choosing it.

Listed on Amazon as: 9V Battery Powered Memory Saver for Car Battery Fit for All OBD ll 16-Pin Interface

#10

10. MR CARTOOL E60

Best for: Cable-only emergency power link.

Why it ranks #10: The E60 is identified as an OBDII emergency power-supply cable, but the supplied details do not specify its power input or operating features.

The MR CARTOOL E60 is supplied as an OBDII vehicle emergency power supply cable, giving buyers a cable-based route for maintaining power during battery work. Its listed identity is specific: model E60, with a cable included. The supplied details do not establish a display, internal battery, or extra operating features.

As a cable rather than a listed self-contained power unit, the E60 suits a workflow where the buyer already has an appropriate backup supply and wants an OBDII connection for the vehicle. The product information identifies it as an emergency power supply cable and lists a cable among the included components. Since no cable length, voltage display, or protection features are specified, those details should not be assumed when planning a battery replacement.

Skip it if you want visible voltage and current readings; the MR CARTOOL B80 lists a real-time voltage and current display.

Choose the E60 if your battery-service setup calls for an OBDII emergency power cable and you can source the backup power separately. Its supplied information is sparse, so it is not the choice for buyers requiring documented cable length or monitoring features.

Listed on Amazon as: MRCARTOOL E60 OBDII Vehicle Emergency Power Supply Cable Car Memory Saver