Li-Ion observation

[Eband]

'observed that the Li-Ion batts' used on high quality HD power tools, Yard equipment etc get quite hot with full power draw use to 'empty'. This is followed by the matching charging stations indicating temperature sensor prevents their charging until cooled. I presume well engineered batt/charger systems all have this temp protection for charging ( don't know about Specialized?) .

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'wonderin' if waiting for batts' to 'cool off' after a large power drain - bike ride, would be recommended.
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... and if recent spate of Li-Ion fires could be related to charging hot batts' ?

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'conventional' Lead-Acid and similar batts do heat up when charging - not from discharging.

 

[fooferdoggie]

'observed that the Li-Ion batts' used on high quality HD power tools, Yard equipment etc get quite hot with full power draw use to 'empty'. This is followed by the matching charging stations indicating temperature sensor prevents their charging until cooled. I presume well engineered batt/charger systems all have this temp protection for charging ( don't know about Specialized?) .

.
'wonderin' if waiting for batts' to 'cool off' after a large power drain - bike ride, would be recommended.
.
... and if recent spate of Li-Ion fires could be related to charging hot batts' ?

.
'conventional' Lead-Acid and similar batts do heat up when charging - not from discharging.

you're not going to get a bike battery hot in use unless it's 120 degrees outside. a cheap battery may heat more but only the surrounding air will heat it up.

 

[fauconnier]

Power tools need a fast charging rate, sometimes in 1/2 hour. That is faster than 1C. Fast charging generate heat. Most E-bike chargers charge at 0.1C to 0.25C, 5 to 15 times slower than a power tool charger, a very soft charging rate.

 

[Stefan Mikes]

Specialized batteries are equipped with several levels of the overheat protection. Firstly, an internal damage or overheating is detected by the charger, and the charging stops (I could observe it on my oldest Vado battery, which got internally damaged because of a bad cell after almost 4 years of heavy use).

Then, there comes the thermal battery protection. Figuratively speaking, the battery has "yellow" and "red" warning zones (these are not visible to the rider unless it is a pre-Mastermind Turbo e-bike, and the e-bike is being monitored by BLEvo app). If you were climbing very steep hills in Turbo mode on a very hot day in the sunshine, the assistance would be cut-off at the "red zone" to let the battery cool off. I need to mention no Specialized battery I own (and I own quite a few) has ever gone into the "red zone", although it was in the "yellow zone" a couple of times in high mountains on hot days.

 

[PDoz]

you're not going to get a bike battery hot in use unless it's 120 degrees outside. a cheap battery may heat more but only the surrounding air will heat it up.

I managed to get a giant battery to switch itself down due to heat on a measely 40 c day (104 in ancient speak) . Admittedly I was repeatedly climbing 350 m over 3.5 km at pull power....

 

[il Munduato]

'observed that the Li-Ion batts' used on high quality HD power tools, Yard equipment etc get quite hot with full power draw use to 'empty'. This is followed by the matching charging stations indicating temperature sensor prevents their charging until cooled. I presume well engineered batt/charger systems all have this temp protection for charging ( don't know about Specialized?) .

.
'wonderin' if waiting for batts' to 'cool off' after a large power drain - bike ride, would be recommended.
.
... and if recent spate of Li-Ion fires could be related to charging hot batts' ?

.
'conventional' Lead-Acid and similar batts do heat up when charging - not from discharging.

As stated by others the charging and discharging rates of tool batteries is much higher than on ebike batteries so the heating issue is far less prevalent. Sure charging a hot or warm battery isn't going to make things better but the fires are mostly caused by over charging, incorrect chargers or the failure of the minimal safety features implemented on less expensive batteries. Every rechargeable battery guide I have ever seen no matter the battery type state to let a just used battery to rest before charging. This is especially true for those used at a high discharge rate.
Discharge a lead acid battery or any other type at a continuous high rate and it too will get warm.

 

[Eband]

... thanks for adding to the cerebral 'data base'.
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( waiting for bike batt to recharge)

 

[fooferdoggie]

I managed to get a giant battery to switch itself down due to heat on a measely 40 c day (104 in ancient speak) . Admittedly I was repeatedly climbing 350 m over 3.5 km at pull power....

I rode with the ground at 135 degrees and the air at 115 and the bosch battery was fine. I was not though.

 

[6zfshdb]

Quality e-bike batteries, used on most "high end" bikes, have thermal protection built into the BMS. Cheap batteries may or may not have this protection.

 

[PDoz]

Quality e-bike batteries, used on most "high end" bikes, have thermal protection built into the BMS. Cheap batteries may or may not have this protection.

Which DOES NOT help when the car is parked up the top of heart attack hill because you've been shuttling the kids all day! The giant drops back to low output, and a few minutes later stops.