Custom S pedelec battery charging

[Stradaman]

My brother was given a custom made Spedelec from his friend last week. His friend literally had it for a week put 10 miles on it and then bought a vehicle and decided he no longer needed it so let my brother have it.

Took it for a test ride yesterday and its insane!

It comes with 2 10,000mah batterys and a strange charger with all sorts of readouts,

Anyway we have no idea how to set it correctly so that it charges the battery property (its not fully charging the batterys) just wondering if anyone could shed some light on it.

The voltage and current are adjustable as well as a few other things that dont understand

What does he need to set this thing at so batterys charge properly?

Any info would be appreciated

 

[Nealh]

Oh dear !!!
Your brothers friend should have given you a thorough guide on to how to use them, if he understood the risks they can carry.

You have been given a pair of 10ah lipo's ( lithium polymer) a slightly more risky and dangerous chemistry version compared to lithium ion.
The batteries are RC hobby one which a few including myself use.

Your ones are 6s 25,2v (6 cells in series)l pouch cells and when joined/connected correctly gives you 50.4v x 12 in series 10ah/480wh battery.
Each pack will have max charge of 25.2v, each cell will charge up to 4.2v
(6 x 4.2 = 25.2v). If possible set the charge to charge to max 4.15v per cell or 24.9v per pack to give a bit of leeway and longer battery life.

The screen setting very top for PB is for lead acid, you need to scroll thru the menu so that it says lipo.
Voltage if possible set it to 24.9v for charging.
Set the current rating to between 5 - 10a for charging (charging is quicker with higher current amps), but no more then 10amps.
Capacity reading you may not under stand but it just tells you how much charge it has taken to top up.

If the bikes has an lcd screen with voltage read out don't go below 3.6/3.7v perc cell which is total pack voltage of 43.2/44.v when discharging.

There re a few do's and dont's with these cells.
1. Don't abuse them by over charging , discharging or dropping them.
2. Keep them ideally in a fire proof metal box or some where safe in a dry cool place. Not in the house. ( I store mine in a metal tool box wrapped in a fire blanket ).
3. When not in use store at voltage of 22.8v, don't leave them in in a fully charged state.
4. Never leave them to charge unattended by leaving the house but keep an eye on the charging every 10 or 15 minutes.
5. Beat to charge them up just before you plan to ride.

If you don't respect these packs they can cause fires and burn houses down, generally they are safe but there has been the odd horror story.

 

[Nealh]

Read thru this tutorial form the massive and knowledgeable Endless-Sphere forum.
https://endless-sphere.com/forums/viewtopic.php?f=14&t=52240

 

[Stradaman]

Wow! Had no idea batterys could be so dangerous.

@Nealh thanks alot for the insight mich appreciated. I'll be passing this onto him right now before he does any damage.

Is there any way he can replace the batteries to lithium ion or a safer stable type / brand of lipo battery at this point Without having to mess around with the bikes wiring?

 

[Nealh]

If they are looked after and given respect they are relatively quite safe, if the basics I have outlined are adhered to then they should provide 18 - 38 months of use. No polymer is any safer main reason why lithium ion is used is the hard casing of the battery and the chemistry is more stable, a bit more forgivable.

The main difference is though is lithium ion batteries/packs have a BMS (pcb) which regulates the charge and discharge, they come with a simple low amp charger (typically 2 -4a) which is plug and play with no settings to mess up.

 

[Nealh]

See how he gets on and if you need more info/help, just post away and we will try to guide /help out.

 

[anotherkiwi]

Some other things that come in handy are alarms set to go off when a cell reaches 3.65v and a Wattmeter. The most useful tool is a thing called a Battery Medic which gives the voltage reading for each cell in a brick and can be used to balance the voltages.

Another important thing is to not let the cells get out of balance with each other, mine are always within 0.03v of each other (the black ones 0.01v). As said above charged to 4.15v per cell and discharged to 3.65v. The green ones are good for 80% of the Ah printed on the packaging and the black ones 90% (have had 9300/10000 mAh) so what you see is a 16 Ah 36v battery. I also use them as an 8 Ah 36v battery and a 8.5 Ah 44.4v battery. Most often I charge after having used 5 Ah or 12 Ah for the big one above.

I have been using the above for just over 2 years. I used to charge in the oven because I didn't have an outdoors. Now that I have an outdoors I charge them there...

 

[Nealh]

Lipo is nothing to be afraid of, just a case of being familiar of how they should be cared for and treated.
I have a pair I use that have been modified to accept a BMS to make my charging simpler and easier.
I also have a small 4ah high output one I use for my palm size Arduino spot welder and it also easily jump starts my car when I have a flat battery.
Smaller ones I also use in my apiaries when treating my bees for pests and viruses.
If you put your mind to it they have some very good uses at a fraction of the weight and size of other battery types.