Improvements relating to the Electric Propulsion of Vehicles.
Year: 1897

page_text: Date of Application, 15th Oct., 1897-Accepted, 20th Nov., 1897
COMPLETE SPECIFICATION.
Improvements relating to the Electric Propulsion of Vehicles.
I, FRIEDRICH WILHELM SCHNEIDER, Engineer, of Triberg, Baden, in the Empire
of Germany, do hereby declare the nature of this invention and in what manner
the same is to be performed to be particularly described and ascertained in and
by the following statement:-
Both in the working of electric vehicles by accumulators alone and also in the
mixed system of accumulators and current supplying conductors, the batteries,
when starting, were mostly arranged in parallel in multiple groups, in order to
preserve the cells and not to diminish their efficiency. It is a well known fact,
that the successive connecting up of such groups in tension is accompanied by
shock or jerk which is not agreeable to the passengers and has an injurious effect
on the motor. For these reasons the successive insertion of multiple groups in
the circuit has already been abandoned in the working with accumulators alone
and a single group is used with which the circuit switch can be formed in a
simpler and easier manner, but the current discharge when starting, is still too
high and also the jerk is not entirely avoided. In the mixed system there has
therefore been used only a battery of which all the elements are connected in ten-
sion, avoiding these inconveniences.
While the vehicle is taking current from the conductor the motor is supplied
directly from the conductor and the battery is changed in parallel with the motor.
With this method there is only the one disadvantage, that when starting on part
of the course not provided with the conductors the current discharge rises to five
or ten times the normal, whereby the capacity and the efficiency of the battery
are considerably impaired and the cells are more liable to injury. It is the
purpose of this invention to avoid these faults while keeping to the simple method
of putting into circuit.
In this invention there is used a main battery and an auxiliary battery. The
first battery is so estimated, that it can provide the working power with a normal
current discharge for the desired time and that it can also be charged in a certain
prearranged duration of time. The auxiliary battery is composed of very small
elements preferably of the Plante system with extremely large surface when it
is being charged it is put in circuit parallel to the main battery. As the auxiliary
battery is charged in a very short time, its counter tension soon augments so that
the whole charging current goes into the main battery. When starting this aux-
iliary battery is put in circuit also parallel to the main battery and, as its tension
is somewhat higher than that of the main battery it provides the great current
quantity to be delivered suddenly when starting. After having started, the
auxiliary battery is put out of circuit and can again recover until the next start.
The auxiliary battery has as long a duration of working as the main battery, since
If for instance the
the current loads to be received by it endure only a short time.
main battery, when starting had to give in the first minute 120 amperes, the effect
on it is greater than if the battery has to give for five minutes a normal current
discharge of 15 to 20 amperes per minute. But if when starting, the auxiliary
battery, which is constructed in the present case for a high current discharge is

page_text: put in circuit parallel with the main battery, 80 to 90 amperes are delivered by the
auxiliary battery and the main battery has hardly to give more than its normal
quantity. The main battery, which in the first case would work for hour, will
be sufficient in the other case for 1 to 2 hours. It is thus evident, that the present
arrangement of putting an auxiliary battery into circuit makes the working very
economical and will reduce considerably the cost of a seasons expenses.
The following example will explain the preceding statements by means of the
annexed diagram.
The main battery a is for instance one of 80 ampere hours with 30 amperes of
normal discharge power and having a weight of about 1500 kg. The auxiliary
battery is such that for ten times the current delivery at each start it can dis-
charge at the rate of 60 amperes for 10 to 12 ampere hours and weighs about
300 kg. The battery a consists for instance of 180 elements, whilst the battery b
has 200. The electrodes of the battery a are constructed for discharges of one to
two hours duration those of the battery have however, as already mentioned
before, an extremely large surface and are formed strictly on the Plante system,
so that they can easily give a high current discharge.
When starting on a part of the course where there is no conductor both batteries
are put in circuit in parallel as shown in the position IV of the starter c, of which
the cover is represented as removed. As soon as the normal velocity is attained,
the auxiliary battery is put out of circuit, so that only the battery a remains
working, as in position V. As the battery 6 has a considerably higher tension,
than the battery a, the first will receive the whole current load when starting,
whilst the main battery is only under normal load. The auxiliary battery b
can again recover until the next start. When the vehicle enters the part of the
course where there is an over ground or underground conductor the two batteries
are to be put again in parallel into circuit as in position 1. The motor d is sup-
plied by the conductor and the batteries a and b are charged parallel to the motor:
The battery will be soon charged and its already high tension will be still aug-
mented. When both batteries are charged, they are put out of circuit and the
motor is driven from direct conductor sec position II. Position III indicates the
circuit closure in the position of rest; VI is the position when the vehicle moves
backwards.
Having now particularly described and ascertained the nature of this in-
vention and in what manner the same is to be performed I declare that what I
claim is:-
The improvement for the working of vehicles with accumulator propulsion, in
which the main battery, when starting, is put in circuit parallel with a small
auxiliary battery constructed for quick discharge, for the purpose of receiving
the current load, at the start, essentially on the auxiliary battery and thus sparing
the main battery and augmenting its efficiency.
Dated this 15th day of October 1897.
HERBERT HADDAN & Co.,
18, Buckingham Street, Strand, London, W.C.
Agents to Applicant.