While lithium-ion batteries naturally degrade (or age) over time, finding the root causes of abnormal battery degradations or failure is not trivial due to the sheer complexity of battery technologies and the many factors affecting battery lifespan and condition.
We know by now that battery health issues can often be linked to battery care and maintenance. But is the degradation happening gradually over the life of the battery, or quickly and unexpectedly? What are early signs and causes of accelerated battery wear, which could lead to battery failure and require a costly battery replacement?
Interested in this topic, I've gathered a list of common battery problems along with potential causes (and remedies) which have helped me so far. Here it is.
SUGGESTED E-BIKE BATTERY CARE AND TROUBLESHOOTING TIPS
COMMON BATTERY ISSUES
- Battery doesn’t take you as far as it did when it was new.
- Battery health % or capacity is decreasing abnormally and battery feels like it's draining faster.
- Battery doesn’t charge as fast as it did when it was new, or cannot be fully charged.
- Battery is not holding or maintaining its charge.
- Battery generates error codes on the bike's display or controller.
- Blinking LEDs (or no lights at all) on the battery pack.
TIP #1 - CHECKING BATTERY HEALTH
I would check the health of the battery by measuring its voltage over time and inspecting the battery temperature.
To do that with my Bosch-powered bikes, I would have my LBS periodically run a full motor and battery diagnostic report to gather state of health or capacity, voltage, min and max temps. Some dealers use a BCT (Battery Capacity Tester) tool to assess battery health.
I would keep a history of the measurements collected over time, starting when the bike/battery was new for comparative analysis and early detection of any abnormal degradations.
TIP #2 - FINDING DEGRADATION CAUSES
If battery health % or capacity measured seem lower than expected, I would try to identify the causes or culprits of an accelerated (abnormal) degradation and then make corrective actions.
I would try to assess the severity of the degradation and determine if the battery is failing (and may need to be replaced) or if I just need to improve how I take care of my battery going forward. See
best practices and tips for battery care here.
Keep in mind though that a 5 to 10% capacity loss over 3 years, or a 10 to 20% capacity loss over 6 years when given proper care, could be considered 'normal'. Refer to your
battery warranty conditions to find out the capacity guaranteed by the manufacturer over a given number of years.
I've outlined below some of the major degradation causes for batteries, sorted by severity (from more to less severe):
- Time spent at very low state of charge. Has the battery been over-discharged (10% or less) while in use or left discharged in storage for an extended time period? Has the battery often been recharged from very low charge levels, basically running the battery nearly empty on most rides?
Time spent in very low temperatures. Has the battery been charged, discharged (ridden) or stored at low temperatures below 0°C (32°F)?
Time spent in high temperatures. Has the battery been charged, discharged (ridden) or stored above 35°C (95°F) heat?
Time spent at very high state of charge. Has the battery been left fully charged (100%) for a long period of time?
Number of charging cycles. Has the battery reached or exceeded the max number of useful charge cycles per the manufacturer warranty limit? See here.
High charging current. Has the battery often been charged using a fast charger (6A-10A) rather than a 2A or 4A charger?
High discharging current. Has the bike been ridden with the highest motor assistance most of the time e.g in Turbo mode all the time?
Battery age/cell aging. How old is the battery? Find the age of your Bosch battery here. Has the battery exceeded the number of years under warranty? See here. Was the battery left on the shelves for several years before getting sold to the customer or being fitted in the bike?
TIP #3 - READING BATTERY ERROR CODES AND FLASHING LEDS
Understanding the error code shown on the bike display or the blinking lights on the battery itself is critical for troubleshooting battery issues.
If the ebike shows a battery-related error code on the bike display/controller, or if I notice flashing LED lights on the battery pack, I would check the battery manufacturer's Customer Support or Help Center site to find details about the error, what could be causing it, and what corrective actions I should take.
As an example, here is a link to the Bosch support site where you can search a specific error code and find details about it. Each manufacturer offers a similar service.
www.bosch-ebike.com
I've listed below common battery-related error codes and LED flash codes for the Bosch CX Gen 4 non-smart motorization.
ERROR CODES - Bosch battery
- Error 423 Battery pack connection problem. Check electrical connections and clean contacts.
Error 540 Battery pack error. Switch off the ebike, remove the battery pack and then reinsert it. Restart the ebike.
Error 602 Battery pack error while charging. Unplug the charger from the battery pack. Restart the ebike. Plug the charger back into the battery pack.
Error 603 Internal battery pack error, sometime while charging. Unplug the charger, stop and restart the ebike.
Error 605 Battery pack temperature error, sometimes while charging. The battery is outside of the permissible temperature range. Unplug the charger and switch off the ebike to allow the drive unit to either cool down or heat up to the permissible temperature. Restart the ebike.
Error 606 Battery pack temperature error. Check the wiring. Restart the ebike.
Error 610 Battery pack temperature error while charging. Restart the ebike.
Error 620 Battery pack voltage error. Replace the charger.
Error 640 Charging error. Restart the ebike.
Error 655 Internal battery pack error. Switch off the ebikes. Remove the battery pack and reinsert it. Restart the ebike.
LED FLASH CODES - Bosch battery
- 3 LEDs flashing. Battery pack too warm or cold. Disconnect the battery from the charger until the charging temperature range has been reached. Do not connect the battery pack to the charger until it has reached the permissible charging temperature.
2 LEDs flashing. Battery pack is defective. Battery may need replacement.
No LEDs on when charging. Charger plug is not inserted correctly or battery contacts are dirty. Check all plug connections. Carefully clean the battery contacts using a damp cloth.
No LEDs on when charging. Wall socket outlet, cable or charger defective. Check household voltage, have charger checked at your bike dealer, replace the charger as needed.
No LED on when charging. Battery pack is defective. Have the battery checked at your bike dealer, replace the battery as needed.
No LEDs on when pressing the Power button. Battery pack may be fully discharged or may be defective. Try charging the battery for an hour or so. If the battery is not charging (still no LEDs on when pressing the Power button), have the battery checked at your bike dealer, replace the battery as needed.
TIP #4 - RESETTING THE BATTERY
To clear a battery related error, I would try resetting the battery. With Bosch batteries, after removing the battery from the bike, a battery reset is done by
pressing and holding the battery power button for 10 seconds and then reinstalling the battery in the bike.
If the power button is not immediately visible or accessible, you may need to use a tool e.g. screwdriver, small punch or thin rod, to reach and gently press the power button through the hole or opening in the battery cover.
TIP #5 - CONSULT YOUR EBIKE OWNER'S MANUAL
Read what your ebike/battery manufacturer says about battery care, maintenance and problem troubleshooting.
Take a look at this post for manufacturers guides and other resources available to e-bike owners.
TIP #6 - ASK A PROFESSIONAL
Always reach out to your nearest bike shop/dealer or battery manufacturer for professional expertise and assistance with using your battery, troubleshooting or resolving battery-related issues. Don't rely on contents posted on social media and public forums for professional advice. In other words, take everything you read or watch on social media with a grain of salt!
WHAT'S ALSO NEW IN THIS THREAD?