Clue contest No 39

Knock around? Yes. It leads to a cell (7)

BATTER+Y. Def is "A CELL"

Beating cake mix, sort of (7)

BATTER = 'cake mix', -Y = 'sort of'. def = 'beating'.

Unmarried subject stopping by for series of tests (7)

Def: series of tests, [-m]ATTER ‘stopping’ B-Y

Unusable if flat as a pancake? (7)

DD "unusable if flat" (flat battery...), "as a pancake" (Batter-y, whimsically)

At the empty roadside serviced by the AA? (7)

[AT+TE(the, empty)+R(road, side)] put into (serviced:mated) BY. Def: The AA? (DBE, battery size)

Assault as Royal Marine abandons Matt Berry carelessly (7)

([M]ATTBE[R]RY)* carelessly

Assault partner in cell (7)

double definition: 'assault' is the partner of 'battery' in the legal phrase 'assault and battery'; 'in' is a link word suggesting that assault's partner can be found in a synonym for 'cell'

They save Charli's second "Brat" remix, it could re-energise radio (7)

T(-H)EYBRAT* (THEY minus second letter in CHARLI); def = "it could re-energise radio"

Crazy about emergency room series (7)

BATT[ER]Y

Full of undercooked cake with limited space for layers? (7)

BATTER-Y def = limited space for layers?

British treaty broken, causing attack (7)

B (British) + (TREATY)* (broken)

During sound times, term from the Right blows (7)

def = blows | (T,T + (th)E + R) in BAY

Beating of percussion section (7)

DD

Power supply box depleted the outside repository (7)

Power supply=def. Box=BAT. depleted the=TE. outside repository=RY

Touching up Rihanna’s bottom secures a charge of assault (7)

BATT(RE<)Y = a charge of assault (law). Touching = concerning; batty = (West Indian) bottom

Hit crack doped with ecstacy — it'll give you energy (7)

BAT (hit) + TRY (crack) containing E(cstacy)

Openers for Bangladesh are tormenting English in test series (7)

B_ A_ T_ + T-E(nglish)-RY; "series"

Swimmer abandons loop in harbour as it drains (7)

Def: it drains; [O]TTER in BAY

Prepare to deep-fry last slice of pricy mignon? (7)

Def: mignon? (DBE) / WP: BATTER (v., prepare to deep-fry) Y (last slice of pricY)

Charge takes charge (7)

Double definition - criminal charge / rechargeable battery

Assault sounds like excessive praise (7)

Def is 'Assault'. sounds like 'FLATTERY'

Where bats go on holiday? (7)

Whimsical def. If a cat goes to a cattery….

Weapons treaty torn up after start of bombing (7)

Def = weapons; anag of TREATY; start of bombing = B

Set strike coordinate (7)

Set (def) = strike (BATTER) + coordinate (Y)

Try and beat, performing this? (7)

Def: this? (extended def). Anagram (performing) of TRY + BEAT

Regrettably, a mixture without large stirring can give a soggy Yorkshire pud (7)

Subtraction anagram: 'regrettably a' - 'large' (indicators: 'mixture', 'without', 'stirring' ; a soggy Yorkshire pud could be whimsically said to be 'batter-y'

Ill-treat chaps close to striking? (7)

ill(anagrind)-treat>ATTER chaps(insertion) close to>BY striking:def>>b{atter}y

They may need to recharge? Treat by massaging (7)

Definition: they may need to recharge? Anagram (massaging) of TREATBY

Variety gained by eating exotic treat (7)

def: 'variety' from BY around anagram of TREAT

Try and beat organised crime (7)

TRY + BEAT anagram = Def.

Where Burmese possibly headed following British attack (7)

DEF: Attack (c)ATTERY (where Burmese may be - headed/top lopped off) following B (British)

One in twenty finally makes selection (7)

BATTER (‘one in’ in cricket)+Y (last letter of twenty) def=selection

'It could be sticky end for Mandy' reveals current source (7)

BATTER (it could be sticky) + Y (end of Mandy) = BATTERY (current source - as in source of electrical current)