The "Standby Drain" Mystery
Normally, a healthy lithium-ion battery should retain most of its charge for weeks or even months when disconnected. If your battery discharges within seven days while sitting on a shelf, the issue is narrowed down to Internal Quick Discharge.
Potential Causes:
Faulty Battery Cells: If one or more cells within the pack are damaged or aging prematurely, they can create a "parasitic" drain on the healthy cells.
BMS Malfunction: The Battery Management System (BMS) is the "brain" inside your battery. If it is faulty, it may consume excessive power while monitoring the cells, even when the battery isn't in use.
Internal Short Circuit: Micro-shorts within the battery casing can cause energy to bleed off as heat, leading to a rapid drop in voltage.
How to Troubleshoot the Issue
Before reaching out for a replacement, perform this simple diagnostic test to confirm the fault:
Full Charge: Charge the battery until the indicator shows it is 100% full.The Isolation Test: Do not install the battery into the bike. Leave it in a cool, dry place for exactly one week.
Voltage Check: After the week is up, use a multimeter to test the battery voltage.If the voltage has dropped significantly (e.g., from 54.6V to 48V or lower for a 48V system), the battery itself is the culprit, not the bike’s electronics.
How to Get It Fixed
Because e-bike batteries are complex and potentially hazardous to open, you should never attempt to repair the internal cells yourself.
If you are experiencing this rapid discharge, you should contact the manufacturer's technical department immediately. For Bodywel owners, email the after-sales team at support@bodywel.com. Provide them with:
Your initial voltage after charging.The voltage reading after one week of standby.Your order details for warranty verification.
A Note on Riding Range
If your battery stays charged while sitting but dies quickly while riding, the cause is likely different. In those cases, check your tire pressure, reduce your load weight, and consider how frequent braking or steep hills are impacting your mileage.
However, for a battery that dies on the shelf, professional support is the only safe way forward.
