Mobile Car Battery Replacement Reading & Berkshire
A flat or failing car battery is one of the most common causes of a non-starting vehicle. We carry a full range of replacement batteries and come to your home, workplace or wherever the car is to test and fit the correct unit.
Battery Testing First
Before fitting a replacement battery, we test the existing one using a conductance tester — this gives a precise measure of the battery’s state of health, not just current charge. A battery that has been jump-started and driven may read a full charge but have degraded cells that will fail again within days.
We also test the alternator charging output (should be 13.8–14.4V at idle) to confirm the battery is the source of the problem, not the charging system.
Battery Types We Supply and Fit
Standard Flooded Lead-Acid
For older vehicles (pre-2010, no stop-start) that specify a conventional battery. Lowest cost.
EFB (Enhanced Flooded Battery)
Required for vehicles with stop-start systems where the manufacturer’s original specification was EFB. EFB batteries handle partial charge cycling better than standard batteries and recover from deep discharge more reliably.
AGM (Absorbed Glass Mat)
Required for vehicles with advanced stop-start, regenerative braking or high electrical loads. AGM batteries deliver greater cold cranking amps, handle deeper discharge cycles and recover faster. BMW, Mercedes-Benz, Audi (A6, A7, A8), Volkswagen Touareg and many Volvo models specify AGM as original equipment.
Fitting EFB or AGM in Non-Spec Vehicles
Fitting a higher-spec battery than specified (e.g. an AGM in a car that calls for a standard battery) will not harm the vehicle. Fitting a lower-spec battery in a car that requires EFB or AGM will cause premature failure within months.
Battery Registration and Reset
BMW, Mercedes-Benz, Audi, Volkswagen, Seat and Škoda vehicles require battery registration via a diagnostic tool when the battery is replaced. This tells the battery management system (BMS) the specifications of the new battery so it can manage charging correctly. Skipping this step causes overcharging, reduced battery life and premature failure. We carry out battery registration as standard.
Pricing
| Battery Type | Price Fitted (typical) |
|---|---|
| Standard flooded | from £85 |
| EFB (stop-start) | from £115 |
| AGM (premium vehicles) | from £145 |
Prices include supply, fitting, old battery disposal and registration/reset where required.
Disposal
We take away the old battery for proper recycling. Lead-acid batteries are hazardous waste — they should not go in general refuse. All our batteries are disposed of through licensed waste carriers.
Book Battery Replacement
Call 07305 523333. We cover Reading and all Berkshire towns. If your car will not start, we can usually attend on the same day. Bring the registration number and we will confirm the correct battery specification before arrival.
Areas we cover
- Mobile mechanic in Reading
- Mobile mechanic in Wokingham
- Mobile mechanic in Newbury
- Mobile mechanic in Basingstoke
- Mobile mechanic in Bracknell
- Mobile mechanic in Tilehurst
- Mobile mechanic in Caversham
- Mobile mechanic in Earley
- Mobile mechanic in Woodley
- Mobile mechanic in Henley-on-Thames
- Mobile mechanic in Twyford
- Mobile mechanic in Thatcham
Frequently asked questions
How do I know if my car battery needs replacing? +
Common signs are slow engine cranking on startup, dashboard warning lights, electrical components behaving erratically, or the car not starting at all. A battery test takes 2 minutes and gives a clear pass or fail result — we test before replacing.
What type of battery does my car need? +
Modern vehicles — particularly those with stop-start systems, regenerative braking or large electrical loads — require EFB (enhanced flooded battery) or AGM (absorbed glass mat) batteries. Fitting a standard flooded lead-acid battery in a car that requires EFB or AGM will cause rapid failure. We confirm the correct specification before fitting.
Will replacing the battery cause any problems with the car's electronics? +
On most modern vehicles, battery replacement may require a reset or registration procedure using a diagnostic tool — particularly BMW, Mercedes-Benz, Audi and Volkswagen Group vehicles. We carry out this procedure as standard. We can also use a battery support unit to maintain power during replacement, preventing adaptive memory loss in ECU systems.
How long does a car battery last? +
The average car battery lasts 3–5 years. Batteries in vehicles with high electrical loads, stop-start systems or frequent short journeys tend to fail sooner. Cold weather accelerates failure in weakened batteries.