Bosch Battery/Charger issue

[robwalley]

Won't seem to charge past 39v. All cells I can reach with the multimeter read 3.89v, but I cannot read the accumulative voltages, the pins are just too small for the multimeter.

Also, although the incoming voltage from the charger also reads 39v, there is a third pin to/from the charger, so DC voltage is only turned on at the charger when a specific signal is received from the BMS, this makes it very difficult (thanks Bosch) to diagnose, for all I know this voltage isn't fixed at 42v and is increased from the charger as required (how else do they justify £140)

I actually suspect the charger rather than duff cell or BMS, anyone in the Gloucester area with a Bosch active charger/battery so I can see quickly where the issue lies?

Don't worry about the fifth charge light being on, it's just the camera capture moment, the fifth light keeps blinking forever indicating incomplete charge, I can also assume that all lights solid indicates full charge as there are no lights on the charger or anywhere else to indicate completed.

The bike is my wife's Cube Hybrid, The simplicity of my bafang BBS02 with 2 pin charger is much preferred.

 

[robwalley]

Small update - the fifth battery light does go solid eventually, but individual cells / overall voltage remain 3.92 / 39.1 respectively.

 

[Danidl]

Small update - the fifth battery light does go solid eventually, but individual cells / overall voltage remain 3.92 / 39.1 respectively.

... What is the problem that you are addressing?. If all the five lights illuminate then the battery is charging. What makes you assume that Bosch want the battery pack to go up to 41v .there is a trade-off between high voltage and pack lifetime .

 

[robwalley]

I have had many electric 36v bicycles and all are 42v chargers, that actually includes Bosch's own battery powered mower, currently charging at 41.8v.

On top of this whatever the charger and battery is indicating, the intuvia display states 4/5 on the the power levels and range is not what it should be.

 

[soundwave]

ecycle over in stroud has the bosch diagnostic software so could plug it in and see if it throws up a batt problem.


jimmy at insat can fix/ recell bosch batts old and new but the bms must be ok to do that.

 

[robwalley]

ecycle over in stroud has the bosch diagnostic software so could plug it in and see if it throws up a batt problem.


jimmy at insat can fix/ recell bosch batts old and new but the bms must be ok to do that.

"Insat"?

 

[soundwave]

http://www.bga-reworking.co.uk/insat-li-nmc-ebike-battery-10ah-24v-36v-48v.html

 

[Danidl]

I have had many electric 36v bicycles and all are 42v chargers, that actually includes Bosch's own battery powered mower, currently charging at 41.8v.

On top of this whatever the charger and battery is indicating, the intuvia display states 4/5 on the the power levels and range is not what it should be.

Not trying to be arguementive here but are you really sure you have a problem?
.. how do you know the range is not what it should be?. Has the range dropped from a previous value.., was it a rapid reduction if so.
Certainly after 4 to 5 hrs charging, all 5 lamps should light up and the display LCD should give 5 bars. If there is a descrepency between 5 bars on the battery pack and 4 bars on the display , that seems very wrong.
The suggestion to have it tested on the diagnostic tester at an Bosch outlet seems very sensible to me.

 

[robwalley]

http://www.bga-reworking.co.uk/insat-li-nmc-ebike-battery-10ah-24v-36v-48v.html

TA

 

[robwalley]

Not trying to be arguementive here but are you really sure you have a problem?
.. how do you know the range is not what it should be?. Has the range dropped from a previous value.., was it a rapid reduction if so.
Certainly after 4 to 5 hrs charging, all 5 lamps should light up and the display LCD should give 5 bars. If there is a descrepency between 5 bars on the battery pack and 4 bars on the display , that seems very wrong.
The suggestion to have it tested on the diagnostic tester at an Bosch outlet seems very sensible to me.

All options are welcome, but there is a discrepancy between the bars on the battery and the LCD display. Unfortunately as the pins are so close together on the accumulative voltage returns on testing, I shorted across two and melted the wires. This makes it way more tricky to fix. Nothing connected to the BMS so no other damage but the individual cells are losing charge overnight with no connections except the total voltage to BMS. Down from 3.92 to 3.82 with no load. Anyway I'll get the charger tested, probably purchase a new battery so the summer isn't wasted and then try to get some money back by getting this one repaired. Looking more and more like a dodgy cell drawing voltage from the rest, no warm cells or BMS though, energy just disappears into thin air.

 

[robwalley]

http://www.bga-reworking.co.uk/insat-li-nmc-ebike-battery-10ah-24v-36v-48v.html

Nothing on their website suggesting battery repair, are you suggesting contacting directly.

 

[soundwave]

there site is a bit naff but yeah give them a ring as they have a 30k spot welder and can use copper or silver to connect the cells.

if you want the pack re celled then you can pick what cells you want in there 40 cells = 14 ah pack with the Panasonic cells.

they will even pick up the pack if needed

 

[Danidl]

All options are welcome, but there is a discrepancy between the bars on the battery and the LCD display. Unfortunately as the pins are so close together on the accumulative voltage returns on testing, I shorted across two and melted the wires. This makes it way more tricky to fix. Nothing connected to the BMS so no other damage but the individual cells are losing charge overnight with no connections except the total voltage to BMS. Down from 3.92 to 3.82 with no load. Anyway I'll get the charger tested, probably purchase a new battery so the summer isn't wasted and then try to get some money back by getting this one repaired. Looking more and more like a dodgy cell drawing voltage from the rest, no warm cells or BMS though, energy just disappears into thin air.

.. when you are getting the charger tested, you should also get the battery tested also. If the charger was connected to the battery at the time of taking your measurements. It was probably in constant current mode and adjusting it's voltage to suit the current, so a reading of 39v would not be wrong. Not happy to hear about melted wiring and how confident are you that the BMS was not involved?. As I understand it, and I may well be wrong, the Bosch units have microcontroller intelligence in the battery pack identifing energy per cell and number of charge cycles , so if it were disconnected, it would need to be reset

You might expect a small voltage drop after a number of hours off charge, it doesn't signify power loss just charge redistribution. The extra amount of energy stored in the last few millivolts per cell is negligible, as a discharge curve for these cells would show.

 

[robwalley]

.. when you are getting the charger tested, you should also get the battery tested also. If the charger was connected to the battery at the time of taking your measurements. It was probably in constant current mode and adjusting it's voltage to suit the current, so a reading of 39v would not be wrong. Not happy to hear about melted wiring and how confident are you that the BMS was not involved?. As I understand it, and I may well be wrong, the Bosch units have microcontroller intelligence in the battery pack identifing energy per cell and number of charge cycles , so if it were disconnected, it would need to be reset

You might expect a small voltage drop after a number of hours off charge, it doesn't signify power loss just charge redistribution. The extra amount of energy stored in the last few millivolts per cell is negligible, as a discharge curve for these cells would show.

Just reading similar stuff online regarding "suicide" tamper chips in Bosch powerpacks since 2014. Mine is probably post this, but close to this date being an active model. The microprocessor certainly gets readings x 10 for every 4 cells to check accumulated voltage is even. Cannot get the battery tested in its current state, although I could desolder the main inputs and charge unbalanced to check total voltage. Also according to my kids who can hear higher pitches the BMS board is buzzing.

 

[soundwave]

i think you will be ok with the bms in that batt but insat can recell the new bosch batts as he can recell them with the bms still powerd.

if the bms looses power on gen 2 batts then its game over and i have only found 2 places that can do them

 

[robwalley]

i think you will be ok with the bms in that batt but insat can recell the new bosch batts as he can recell them with the bms still powerd.

if the bms looses power on gen 2 batts then its game over and i have only found 2 places that can do them

Well the motor is an "active" which is gen2? So how can you tell for the battery pack? Also some of the balance wires are disconnected/melted, but (and I'm not sure) these are read only by the BMS, the main voltage supply is still connected.

 

[soundwave]

all i know is the gen 2 batts bms is tamper proof and the gen 1 batts could be easily re celled as been doing it on the german site for ages now even adding booster packs to them.

best bet is to give jimmy at insat a ring and see what he says as it is the only place that can fix it if it has a gen 2 bms.

 

[robwalley]

all i know is the gen 2 batts bms is tamper proof and the gen 1 batts could be easily re celled as been doing it on the german site for ages now even adding booster packs to them.

best bet is to give jimmy at insat a ring and see what he says as it is the only place that can fix it if it has a gen 2 bms.

Well that couldn't have gone worse. INSAT organised package pickup as they know couriers who carry lithium batteries (INSAT told me this) and are insured (I assumed). Battery picked up and damaged/stolen/lost by UPS somewhere along the way, turned up at INSAT as a empty tube with just the charger and paper work. Not INSAT's fault, but as the retailer who took responsibility for the courier (same as posting goods to you) they are liable. They refused to even discuss and now I'm left with bringing proceedings to get a value of a damaged battery pack. Found a rare one on ebay for half price and while a tad risky is good so far getting new battery miles. Still seems like £300 down the drain (so far)

 

[EddiePJ]

Ref the battery chargers, I have two Bosch chargers, and with one them the light goes out when the battery is fully charged, and with the other it doesn't.

From swapping chargers, it does appear that the one that the light doesn't go out, still charges correctly, but I have no idea why the light doesn't go off.