Is it advisable to always use the RE battery first?

[etgo]

Is it advisable to always use the RE battery first?

or

It is better to use both batteries (RE Batt and Main Batt) at the same time?

 

[Onimaru]

For many smart multi battery devices, the BMS will pull from each battery intermittently. It extends battery life by limiting stress and heat and such.

 

[Stefan Mikes]

Is it advisable to always use the RE battery first?

or

It is better to use both batteries (RE Batt and Main Batt) at the same time?

It really depends.

• If you are on a long demanding ride, it is always recommended to use both batteries together. If you used the RE first on a long ride, I can guarantee the RE would become depleted below 10% when you needed the assistance the most (for example, in the middle of a climb).
• However, it is good to use the RE first if you set off for short rides often. Each of the batteries gets slowly degraded with the growing number of charging cycles. You might notice the main battery gets more charging cycles if you ride the e-bike on the main battery only often. To equalize the number of charges for both batteries, you might choose "Discharge the RE first" until the use of both batteries becomes equal.

If you always ride with the Range Extender, use both batteries in parallel.

 

[Allan47.7339]

I've only used the RE fist setting when I forgot to charge the batteries before going on the next ride. I wanted to make sure I kept enough reserve for the hilly sections but in the end I'm not sure how much difference it made. I think it's better to get used to whichever mode you use so you can interpret how much battery you have left. I prefer to use the parallel mode since it's what I generally use and know how to estimate my range. I used to have a coworker who always said he was too busy to take time to learn how to use his computer tools efficiently. I'm too busy riding my bike to figure out if I'm using optimum battery.

 

[Stefan Mikes]

As I own as many as three Range Extenders, riding on the REs makes sense in my case.

Whenever I go for a long ride, I use the main battery + RE in parallel. However, my daily short rides are done on Range Extenders until the number of recharges on any of them becomes equal. My goal is to save the main battery, especially as Range Extenders are less expensive.

 

[etgo]

@Stefan Mikes, you bring all 3 RE during a ride? Where did you put the extra 2 RE? might get some idea from you.
I plan to bring 2 RE + 1 water bottle in a long ride, but can't decide where to put the 2nd RE.
I don't like bringing any kind of bag during ride. all stuff in the bike only.

 

[Stefan Mikes]

Depending on the ride character, it might be from zero to all three REs. If I need to carry one or two spares, I just carry them in the backpack. They are so lightweight!

Compare that to carrying one or two full power batteries, which requires pannier(s)...

 

[Nomad]

To me if I had a range extender I would tend use it one of to ways. Like the reserve tank on motorcycle oh crap .... wait a minute just turn the lever and head to the gas station or short light trips.

 

[Sparky731]

Depends upon brand? I have a Bosch system and both batteries charge and drain in a parallel scheme according to Bosch.

 

[Stefan Mikes]

Depends upon brand? I have a Bosch system and both batteries charge and drain in a parallel scheme according to Bosch.

It is the Specialized forum
We are talking about the SL Range Extender, which allows both modes.