Herewith a commentary on some work I have been doing on the Vectrix Charger Programming.
I have achieved a limited success in the task of re-arranging some of the charger's performance. This has been with the object of reducing the battery 'damage' whilst charging and also, hopefully, to extend the life and therefore the mileage of the battery before replacement becomes necessary.
It is my view that most of the damage to the battery is caused by heat, and that heat is generated / produced by two means. The first is the heat of the charging process and the second cause is the internally generated heat produced by the battery's internal resistance when current is drawn from the battery.
So far, I have concentrated on the charging process. My aim was to reduce the initial charging current, maintain that current to around 80% of 'full' capacity (24 Ah) and then continue the charge with a further reduced current for a sufficient time to complete the charge process. There will be a 'side effect' of this which is a longer charge time, however, I consider that a longer charge time might be worth accepting if a longer battery life results from this. Bear in mind that charge time, including equalisation, can extend to over eight hours with the Vectrix programme/software.
In terms of the initial charge (up to 80%), reducing the current to 6 to 7 amperes only increase the charge time from 2hrs (empty battery) to 3.5 hrs. This is an increase which I am prepared to accept.
The second stage of charging which involves the ''tr' cool off periods, lasts for one hour, in the earlier software (Version 2012 and thereabouts) this also involved a low rate charge of 3amps. In the 3001 version, this was reduced to zero charge and still runs for the hour (I believe that Vectrix had noticed that the 'tr' at 3 amps was actually causing further heating of the battery).
The third stage of charging is the C.C. (constant current) stage which runs for a preset time or until a preset voltage is reached or until the battery heats up to a preset maximum temperature.
A final charge stage involves the process of Equalisation. The purpose of which is to bring any cells which have 'fallen behind' in terms of charge (i.e. they are not 'Full' whilst other cells are full) up to a genuine fully charged condition.
The main heat producer during the charge process is the latter part of the initial stage ( the part that takes the battery to 80%), this is followed by the Constant Current charge at 3 amps which also produces excess heat. The Equalisation current level is also excessive and contributes yet more heat to the battery.
Vectrix 'engineers' recognised the problem but failed to deal with it mainly due to their over-qualification for the job which they were doing. A common problem with overqualified engineers is that they are full of theory and short on practice. As anyone who is involved in troubleshooting knows, theoretical knowledge and practice experience can often be very difficult to marry together and in all cases, what happens in practice is far more important that what should happen according to theory.
Vectrix engineers attempted to solve the heating problems by 'cooling' the batteries (the plenum chamber fans). They added periods of 'cooling' to the process (the tr.with no current in later software). They programmed in a temperature limit, beyond which the charge was halted and the fans were kept running, but they completely failed to realise that the best way to deal with the problem was to NOT generate the heat in the first place. They were, of course, far more interested in selling a short recharge time that would appeal to buyers. A VERY BIG MISTAKE.
Where does that leave us? Well, working on an earlier version of the software ( I wanted tr. with instruments lit up), I have been able to make a number of alterations to the programme parameters without actually altering the programme routine itself.
I have reduced the initial charge current (C.P.) 6 to 7 amperes (864 watts) and reduced the 'aiming' voltage so that C.P.144 is the voltage limit for the initial charge. At a charge rate of 6 amperes, 80% charge occurs at approximately 144Volts.
I have reduced the 'cool off' current to 1.5 amperes. The 'aiming' voltage is set, within the programme, to equal the C.P. voltage.
I have reduced the Constant Current level to 1.5amperes and increased the maximum time to 4hrs and may yet need to add more time (it was set to around 3.5 previously)
The above changes do increase the charge times, is there really any choice?
Vectrix had set some 'safeguards' in the programme. I have used the word 'safeguard' rather loosely. They had set the maximum battery temperature to 50 degrees Centigrade. By the time that the battery casing, where the temperature is measured, reaches 50 degrees then the internals of the battery are considerably hotter. I don't call that a safe limit.
If the charger 'control' failed then they had a 'safe' limit of 15 amperes and a maximum charge of 32 ah in C.P. mode with a 35 ah absolute limit. What they did not consider was that if the programme 'locks' then even these limits will not help as they will not be applied due to the locked programme.
If the battery temperature exceeded 40 degrees in use (when riding) then the plenum fans where switched 'on'. At 40 degrees C on the battery case, when in use, the damage is already done, as I have already said theory and practice ...?..?..?....?
So much for the Vectrix engineers 'safeguards'
I have incorporated 'safer' limits into the software which I am altering. I have reduced the maximum charger output to 8 amperes. I have arranged for the plenum fans to be always 'on' when the bike is being used. I have set the safe maximum battery temperature (when charging) to 25 degrees C ( it is currently 5 degrees outdoors here just now and rarely exceeds 20 degrees) and I have reduced the maximum ampere hours in C.P. mode to 24.
All in all, a number of changes and hopefully for the better.
The above changes are currently being tested and have so far proved to work as intended. It will be a while before the real effects (a longer battery life with fewer imbalance problems) are available.
The above 'work' has taken longer than I expected, but reverse engineering, in order to find out how a programme works, is not the easiest of subjects and I am still a novice. I have done nothing illegal, all I have done is to make alterations to an existing hex file for my own benefit. I am willing to share my knowledge with you individually so that you too can benefit if you wish. The alterations which I have made can be varied to suit individual requirements (not easy but not too hard either).
This is not a simple process, but I will try to help anyone out there who may be interested in this work. Basically, I have made the alterations directly in the Hex file which is programmed into the bike with the Vectrix Diagnostic Software. The changes to the hex files are written for a specific version and cannot easily be 'fitted' in other versions. Because I have 'downgraded' to an earlier software version, I have lost the estimated mileage readout on the left-hand display and the battery capacity meter (right-hand display) no longer decrements. I have found that the left brake pull that gives the voltage and temperature readout allows me to estimate the remaining battery capacity and I have not been caught out yet.
I am hoping, in due course, to reverse engineer the whole programme. When that is completed, I shall write my own programme to deal with the problems in my own way and will publish the programme as freeware (but that, folks, may take some time)
Dear People at Vectrix,, (I know that you read this column)
Why don't you contact me so that WE can work out YOUR problems together and benefit YOUR business and YOUR customers and perhaps the environment at the same time? I don't even want paying, (although you might like to contribute towards the £150 worth of books I have bought) all I want is a good reliable product. You have nearly achieved that, why not allow me to help you finish the job properly? Contact me through this forum, PLEASE. :-)
And having got that over folks, Merry Christmas and a Happy new year to you all, even to those people at Vectrix.
Keep smiling folks:-)