battery quedtion

[bones774]

hi, on a new older model leftover can you tell if the battery has been used? still in deep sleep? does it really matter? can I the consumer diagnose if its deep sleep? this would be an online retailer so I would only know after receipt of bike. thanks

 

[harryS]

Deep sleep? What's that?

All the batteries that I purchased new come in at nominal voltage. A 36V pack tests 36V. A 48V pack tests 48V.

 

[6zfshdb]

This would depend on the bike brand. Some batteries work with smartphone apps which will tell you the number of charge cycles as well as the battery "health".

You can also look for minor scratches or marks on the battery case which can be an indication of use.

I don't think this really matters as long as the battery meets it's capacity ratings and hasn't obviously been abused.

On some batteries, including the ones I have, the BMS puts them into sleep mode when not used for extended periods. They "wake up" when connected to the charger.

Does the bike come with a warranty? If so, a defective battery should be grounds for a replacement or even the return of the entire bike.

 

[bones774]

Deep sleep? What's that?

All the batteries that I purchased new come in at nominal voltage. A 36V pack tests 36V. A 48V pack tests 48V.

Deep sleep is a term i've read here numerous times in my short time on this forum. First i heard of it also, but i'm new to these battery systems and their controls

 

[bones774]

This would depend on the bike brand. Some batteries work with smartphone apps which will tell you the number of charge cycles as well as the battery "health".

You can also look for minor scratches or marks on the battery case which can be an indication of use.

I don't think this really matters as long as the battery meets it's capacity ratings and hasn't obviously been abused.

On some batteries, including the ones I have, the BMS puts them into sleep mode when not used for extended periods. They "wake up" when connected to the charger.

Does the bike come with a warranty? If so, a defective battery should be grounds for a replacement or even the return of the entire bike.

The bike has warranty but it is a Easy motion Gravel X, and their warranty would be suspect now that they are out of NA market.

 

[rich c]

Deep sleep is a bricked battery isn’t it?

 

[Sierratim]

Deep sleep is a term i've read here numerous times in my short time on this forum. First i heard of it also, but i'm new to these battery systems and their controls

A lithium battery pack is always equipped with a Battery Management System (BMS) that vary is sophistication. All will prevent over charging or under discharging of the battery cells. However, discharging a pack to its lower limit as allowed by the BMS and then storing it for a prolonged time, esp at lower temps, can allow one or more cells to drift below the minimum voltage the charger and/or BMS expects to see for safe charging. These cells are said to be 'a sleep'. As far as a simpler charger - BMS setup is concerned, the battery is dead and can't be recharged. However, more sophisticated setups can detect abnormally low cell voltages and trickle charge these cells back to the point where the pack can be charged as normal. These setups are often said to have a 'Boost' feature. This article speaks to this in more detail.

How might this impact your purchase? If the battery is DOA, it might just be 'a sleep'. The charger setup may have a 'Boost' feature, but this isn't really that common. I'd still try charging the DOA battery with the supplied charger but the most likely outcome in this case is that the supplier would need to send a new battery. Other than a DOA battery, just charge the battery with the supplied charger and let it go for 24 hours or so for the first charge. The charger should have status indicator lights that let you know what's going on.

BTW - I don't charge my bike batteries in the house. The charge setups are in the detached shop, just in case...